我的应用程序中有五个复选框和五个进度条,并根据复选框调用可见性以使进度条可见/消失。那么,在可见性方法中是否有任何替代 if-else 语句的方法,因为在这种情况下,五个复选框中有无限的可能性,所以我必须编写无限的 if else 语句,以使进度条在所有可能性中可见/消失.
例如-如果CheckBox1&checkbox2被选中,则使progressbar2可见 如果选中了 checkbox1&checkbox3,则使进度条2可见
换句话说,如果选中任何一个复选框,我想让进度条 1 可见;如果选中任意两个复选框,我想让进度条 2 可见,依此类推..
import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.view.View;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.ProgressBar;
public class Progress extends Activity {
ProgressBar progressBar1;
ProgressBar progressBar2;
CheckBox checkBox1;
CheckBox checkBox2;
SharedPreferences sharedPreferences;
SharedPreferences.Editor editor;
SharedPreferences setprefsd;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_progress);
setprefsd = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
progressBar1 = (ProgressBar) findViewById(R.id.progressBar1);
progressBar2 = (ProgressBar) findViewById(R.id.progressBar2);
checkBox1 = (CheckBox) findViewById(R.id.checkBox1);
checkBox2 = (CheckBox) findViewById(R.id.checkBox2);
if (setprefsd.getBoolean("FirstCheckBox", false) == true) {
checkBox1.setChecked(true);
updateProgressBars();
}
if (setprefsd.getBoolean("SecondCheckBox", false) == true) {
checkBox2.setChecked(true);
updateProgressBars();
}
}
public void updateProgressBars() {
progressBar1.setVisibility(View.GONE);
progressBar2.setVisibility(View.GONE);
if (checkBox1.isChecked() && checkBox2.isChecked()) {
progressBar2.setVisibility(View.VISIBLE);
} else if (checkBox1.isChecked()) {
progressBar1.setVisibility(View.VISIBLE);
}
}
}
您可以使用三元运算符来使可见性更改更简单(而不是
if
)。
我想这里的方法是计算复选框的数量,然后设置可见性。你只需要像这样改变你的
updateProgressBars()
方法:
public void updateProgressBars() {
int nbCheckboxes = 0;
if (checkBox1.isChecked())
nbCheckboxes++;
if (checkBox2.isChecked())
nbCheckboxes++;
progressBar1.setVisibility(nbCheckboxes >= 1 ? View.VISIBLE : View.GONE);
progressBar2.setVisibility(nbCheckboxes >= 2 ? View.VISIBLE : View.GONE);
}
您正在使用以下结构:
if (myBooleanExpression == true)
不需要
== true
,因为您在此处使用布尔表达式。代替使用:
if (myBooleanExpression)
如果您使用多个具有相同用途的编号变量,您可能需要考虑使用数组。
public class Progress extends Activity {
ProgressBar[] progressBars;
CheckBox[] checkBoxes;
SharedPreferences sharedPreferences;
SharedPreferences.Editor editor;
SharedPreferences setprefsd;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_progress);
setprefsd = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
progressBars = new ProgressBar[3]; // 3, or whatever number you have
progressBars[0] = (ProgressBar) findViewById(R.id.progressBar1);
progressBars[1] = (ProgressBar) findViewById(R.id.progressBar2);
progressBars[2] = (ProgressBar) findViewById(R.id.progressBar3);
checkBoxes = new CheckBox[3]; // 3 or whatever number you have
checkBoxes[0] = (CheckBox) findViewById(R.id.checkBox1);
checkBoxes[1] = (CheckBox) findViewById(R.id.checkBox2);
checkBoxes[2] = (CheckBox) findViewById(R.id.checkBox3);
checkBoxes[0].setChecked(setprefsd.getBoolean("FirstCheckBox", false));
checkBoxes[1].setChecked(setprefsd.getBoolean("SecondCheckBox", false));
checkBoxes[2].setChecked(setprefsd.getBoolean("ThirdCheckBox", false));
updateProgressBars();
}
public void updateProgressBars() {
int nbCheckBoxes = 0;
for (CheckBox cb : checkBoxes) {
if (cb.isChecked())
nbCheckBoxes++;
}
for (int i = 0; i < progressBars.length; i++) {
progressBars[i].setVisibility(nbCheckboxes > i ? View.VISIBLE : View.GONE);
}
}
}
如果您有 3 个场景需要检查 9 次状况。
喜欢:
if (!mCallType.isIncall() && mCallType.isOutcall() && mCallType.isTelecall()) {
glInCall.setVisibility(View.GONE);
glOutCall.setVisibility(View.VISIBLE);
glTeleCall.setVisibility(View.VISIBLE);
} else if (mCallType.isIncall() && !mCallType.isOutcall() && mCallType.isTelecall()) {
glOutCall.setVisibility(View.GONE);
glInCall.setVisibility(View.VISIBLE);
glTeleCall.setVisibility(View.VISIBLE);
} else if (mCallType.isIncall() && mCallType.isOutcall() && !mCallType.isTelecall()) {
glTeleCall.setVisibility(View.GONE);
glOutCall.setVisibility(View.VISIBLE);
glInCall.setVisibility(View.VISIBLE);
} else {
glOutCall.setVisibility(View.VISIBLE);
glInCall.setVisibility(View.VISIBLE);
glTeleCall.setVisibility(View.VISIBLE);
}
那就不要使用“IF, ELSE IF”条件。
最好的替代品是HashMap
HashMap visiblityManager = new HashMap<>(); // Visibility Manage without if else condition. visiblityManager.put(true, View.VISIBLE); visiblityManager.put(false, View.GONE); glInCall.setVisibility((Integer) visiblityManager.get(mCallType.isIncall())); // This Data comes from API or Database. it is a Boolean data. glOutCall.setVisibility((Integer) visiblityManager.get(mCallType.isOutcall())); // This Data comes from API or Database. it is a Boolean data. glTeleCall.setVisibility((Integer) visiblityManager.get(mCallType.isTelecall())); // This Data comes from API or Database. it is a Boolean data.