作为编程的新手，我采用了Android Studio示例代码“BluetoothLeGatt”，整个项目本身就可以正常工作。但是，当我尝试添加一个活动时（我添加了一个java文件，我正确地使用了一个意图来打开BluetoothLeGatt的第一个活动（即DeviceScanActivity.java），然后点击我在新的xml文件中创建的按钮。我把这个新活动作为启动器放在清单文件中，并将DeviceScanActivity放在清单中。在编译期间，没有错误，但是当我在手机上打开apk时，应用程序立即崩溃。我有什么不同的做法？
TestLaunchActivity.java（新的应该先行）
package com.example.android.bluetoothlegatt;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
public class TestLaunchActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.testlaunchactivity);
Button button_startBleGatt = (Button) findViewById(R.id.button_startBleGatt);
button_startBleGatt.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View view) {
Intent gotoselection = new Intent(TestLaunchActivity.this, DeviceScanActivity.class);
startActivity(gotoselection);
}
});
}
}
testlaunchactivity.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<Button
android:id="@+id/button_startBleGatt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_marginTop="80dp"
android:text="start"
android:textAllCaps="true" />
</LinearLayout>
AndroidManifest.xml中
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.android.bluetoothlegatt"
android:versionCode="1"
android:versionName="1.0">
<!-- Min/target SDK versions (<uses-sdk>) managed by build.gradle -->
<!-- Declare this required feature if you want to make the app available to BLE-capable
devices only. If you want to make your app available to devices that don't support BLE,
you should omit this in the manifest. Instead, determine BLE capability by using
PackageManager.hasSystemFeature(FEATURE_BLUETOOTH_LE) -->
<uses-feature android:name="android.hardware.bluetooth_le" android:required="true"/>
<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
<application android:label="@string/app_name"
android:icon="@drawable/ic_launcher"
android:theme="@android:style/Theme.Holo.Light">
<activity android:name=".TestLaunchActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".DeviceControlActivity"/>
<activity android:name=".DeviceScanActivity"/>
<service android:name=".BluetoothLeService" android:enabled="true"/>
</application>
</manifest>
logcat的：
02-18 11:56:18.765 3331-3331/? D/dalvikvm: Late-enabling CheckJNI
02-18 11:56:18.815 3331-3331/com.example.android.bluetoothlegatt D/ActivityThread: handleBindApplication:com.example.android.bluetoothlegatt
02-18 11:56:18.815 3331-3331/com.example.android.bluetoothlegatt D/ActivityThread: setTargetHeapUtilization:0.75
02-18 11:56:18.815 3331-3331/com.example.android.bluetoothlegatt D/ActivityThread: setTargetHeapMinFree:2097152
02-18 11:56:18.815 3331-3331/com.example.android.bluetoothlegatt W/ActivityThread: Application com.example.android.bluetoothlegatt is waiting for the debugger on port 8100...
02-18 11:56:18.825 3331-3331/com.example.android.bluetoothlegatt I/System.out: Sending WAIT chunk
02-18 11:56:18.995 3331-3337/com.example.android.bluetoothlegatt I/dalvikvm: Debugger is active
02-18 11:56:19.025 3331-3331/com.example.android.bluetoothlegatt I/System.out: Debugger has connected
02-18 11:56:19.025 3331-3331/com.example.android.bluetoothlegatt I/System.out: waiting for debugger to settle...
02-18 11:56:19.225 3331-3331/com.example.android.bluetoothlegatt I/System.out: waiting for debugger to settle...
02-18 11:56:19.425 3331-3331/com.example.android.bluetoothlegatt I/System.out: waiting for debugger to settle...
02-18 11:56:19.625 3331-3331/com.example.android.bluetoothlegatt I/System.out: waiting for debugger to settle...
02-18 11:56:19.825 3331-3331/com.example.android.bluetoothlegatt I/System.out: waiting for debugger to settle...
02-18 11:56:20.025 3331-3331/com.example.android.bluetoothlegatt I/System.out: waiting for debugger to settle...
02-18 11:56:20.225 3331-3331/com.example.android.bluetoothlegatt I/System.out: waiting for debugger to settle...
02-18 11:56:20.425 3331-3331/com.example.android.bluetoothlegatt I/System.out: debugger has settled (1315)
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.view.Window$Callback.onPointerCaptureChanged, referenced from method android.support.v7.view.WindowCallbackWrapper.onPointerCaptureChanged
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve interface method 15186: Landroid/view/Window$Callback;.onPointerCaptureChanged (Z)V
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x72 at 0x0002
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.view.Window$Callback.onProvideKeyboardShortcuts, referenced from method android.support.v7.view.WindowCallbackWrapper.onProvideKeyboardShortcuts
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve interface method 15188: Landroid/view/Window$Callback;.onProvideKeyboardShortcuts (Ljava/util/List;Landroid/view/Menu;I)V
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x72 at 0x0002
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to find class referenced in signature (Landroid/view/SearchEvent;)
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.view.Window$Callback.onSearchRequested, referenced from method android.support.v7.view.WindowCallbackWrapper.onSearchRequested
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve interface method 15190: Landroid/view/Window$Callback;.onSearchRequested (Landroid/view/SearchEvent;)Z
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x72 at 0x0002
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.view.Window$Callback.onWindowStartingActionMode, referenced from method android.support.v7.view.WindowCallbackWrapper.onWindowStartingActionMode
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve interface method 15194: Landroid/view/Window$Callback;.onWindowStartingActionMode (Landroid/view/ActionMode$Callback;I)Landroid/view/ActionMode;
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x72 at 0x0002
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.res.TypedArray.getChangingConfigurations, referenced from method android.support.v7.widget.TintTypedArray.getChangingConfigurations
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 783: Landroid/content/res/TypedArray;.getChangingConfigurations ()I
02-18 11:56:20.505 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0002
02-18 11:56:20.515 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.res.TypedArray.getType, referenced from method android.support.v7.widget.TintTypedArray.getType
02-18 11:56:20.515 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 805: Landroid/content/res/TypedArray;.getType (I)I
02-18 11:56:20.515 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0008
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.Context.createDeviceProtectedStorageContext, referenced from method android.support.v4.content.ContextCompat.createDeviceProtectedStorageContext
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 564: Landroid/content/Context;.createDeviceProtectedStorageContext ()Landroid/content/Context;
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0006
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.Context.getCodeCacheDir, referenced from method android.support.v4.content.ContextCompat.getCodeCacheDir
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 570: Landroid/content/Context;.getCodeCacheDir ()Ljava/io/File;
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0006
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.Context.getColor, referenced from method android.support.v4.content.ContextCompat.getColor
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 571: Landroid/content/Context;.getColor (I)I
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0006
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.Context.getColorStateList, referenced from method android.support.v4.content.ContextCompat.getColorStateList
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 572: Landroid/content/Context;.getColorStateList (I)Landroid/content/res/ColorStateList;
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0006
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.Context.getDataDir, referenced from method android.support.v4.content.ContextCompat.getDataDir
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 574: Landroid/content/Context;.getDataDir ()Ljava/io/File;
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0006
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.Context.getDrawable, referenced from method android.support.v4.content.ContextCompat.getDrawable
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 575: Landroid/content/Context;.getDrawable (I)Landroid/graphics/drawable/Drawable;
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0006
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.Context.getNoBackupFilesDir, referenced from method android.support.v4.content.ContextCompat.getNoBackupFilesDir
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 582: Landroid/content/Context;.getNoBackupFilesDir ()Ljava/io/File;
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0006
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.Context.isDeviceProtectedStorage, referenced from method android.support.v4.content.ContextCompat.isDeviceProtectedStorage
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 595: Landroid/content/Context;.isDeviceProtectedStorage ()Z
02-18 11:56:20.545 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0006
02-18 11:56:20.555 3331-3331/com.example.android.bluetoothlegatt I/dalvikvm: Could not find method android.content.Context.startForegroundService, referenced from method android.support.v4.content.ContextCompat.startForegroundService
02-18 11:56:20.555 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: VFY: unable to resolve virtual method 610: Landroid/content/Context;.startForegroundService (Landroid/content/Intent;)Landroid/content/ComponentName;
02-18 11:56:20.555 3331-3331/com.example.android.bluetoothlegatt D/dalvikvm: VFY: replacing opcode 0x6e at 0x0006
02-18 11:56:20.565 3331-3331/com.example.android.bluetoothlegatt D/AndroidRuntime: Shutting down VM
02-18 11:56:20.565 3331-3331/com.example.android.bluetoothlegatt W/dalvikvm: threadid=1: thread exiting with uncaught exception (group=0x415a0d58)
02-18 11:56:20.575 3331-3331/com.example.android.bluetoothlegatt E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.android.bluetoothlegatt, PID: 3331
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.android.bluetoothlegatt/com.example.android.bluetoothlegatt.TestLaunchActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2187)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2236)
at android.app.ActivityThread.access$800(ActivityThread.java:138)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1199)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5095)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:602)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
at android.support.v7.app.AppCompatDelegateImplV9.createSubDecor(AppCompatDelegateImplV9.java:354)
at android.support.v7.app.AppCompatDelegateImplV9.ensureSubDecor(AppCompatDelegateImplV9.java:323)
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:284)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139)
at com.example.android.bluetoothlegatt.TestLaunchActivity.onCreate(TestLaunchActivity.java:15)
at android.app.Activity.performCreate(Activity.java:5231)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2151)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2236)
at android.app.ActivityThread.access$800(ActivityThread.java:138)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1199)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5095)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:602)
at dalvik.system.NativeStart.main(Native Method)
02-18 11:57:07.985 3331-3331/com.example.android.bluetoothlegatt I/Process: Sending signal. PID: 3331 SIG: 9
这是logcat的重要部分 -
FATAL EXCEPTION: main
Process: com.example.android.bluetoothlegatt, PID: 3331
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.android.bluetoothlegatt/com.example.android.bluetoothlegatt.TestLaunchActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
你正在使用Theme.Holo.Light作为你的应用程序，但你的TestLaunchActivity扩展继承AppCompatActivity的Theme.AppCompat。要么将应用程序主题更改为Theme.AppCompat及其后代主题（Light/Dark），它会改变您的操作栏的外观，并为您的所有活动扩展AppCompatActivity，or在您的Activity中扩展TestLaunchActivity。 AppCompatActivity用于支持旧版本的Android APIs。
这里有更多的资源 - You need to use a Theme.AppCompat theme (or descendant) with this activity
除此之外，logcat对日志有多重要的重要性。您可以在debug/info/error中使用过滤器（logcat等）。每当应用程序崩溃时，您都会看到相关的stacktrace错误。错误也以红色打印，因此很容易识别它们。