我有一个 AutocompleteTextView，它工作正常。当我写一个单词时，它会显示相关结果，但我想显示所有项目，而不在 AutocompleteTextView 中写任何单词。我怎样才能做到这一点。
您需要扩展 AutoCompleteTextView，
“当阈值小于或等于0时，阈值为1 已申请。”。
import android.content.Context;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.widget.AutoCompleteTextView;
public class InstantAutoComplete extends AutoCompleteTextView {
public InstantAutoComplete(Context context) {
super(context);
}
public InstantAutoComplete(Context arg0, AttributeSet arg1) {
super(arg0, arg1);
}
public InstantAutoComplete(Context arg0, AttributeSet arg1, int arg2) {
super(arg0, arg1, arg2);
}
@Override
public boolean enoughToFilter() {
return true;
}
@Override
protected void onFocusChanged(boolean focused, int direction,
Rect previouslyFocusedRect) {
super.onFocusChanged(focused, direction, previouslyFocusedRect);
if (focused && getFilter()!=null) {
performFiltering(getText(), 0);
}
}
}
在 xml 中
<AutoCompleteTextView ... /> to <your.namespace.InstantAutoComplete ... />
编辑1
创建名为 InstantAutoComplete 的新类，然后将此代码放入该类中。
在布局 xml 中使用此类，如
然后在您的活动中找到这个小部件（onCreate 方法）。
这里有更好的解决方案
您无需自定义您的
AutoCompleteTextViewautoCompleteTextView.showDropDown()它对我有用：
向您的对象添加下一个事件方法：
myView.setOnFocusChangeListener(new OnFocusChangeListener() {
@Override
public void onFocusChange(View v, boolean hasFocus) {
if (hasFocus)
myView.showDropDown();
}
});
myView.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
myView.showDropDown();
return false;
}
});
这对我来说非常有效，这是解决问题的简单方法：
final ArrayAdapter<String> adapter = new ArrayAdapter<>(getContext(), android.R.layout.simple_dropdown_item_1line, usernameLists);
etUsername.setThreshold(1);
etUsername.setAdapter(adapter);
etUsername.setOnTouchListener(new View.OnTouchListener() {
@SuppressLint("ClickableViewAccessibility")
@Override
public boolean onTouch(View paramView, MotionEvent paramMotionEvent) {
if (usernameLists.size() > 0) {
// show all suggestions
if (!etUsername.getText().toString().equals(""))
adapter.getFilter().filter(null);
etUsername.showDropDown();
}
return false;
}
});
需要调用
requestFocus();该方法强制显示下拉列表。
autocomptv.setOnTouchListener(new OnTouchListener() {
@SuppressLint("ClickableViewAccessibility")
@Override
public boolean onTouch(View paramView, MotionEvent paramMotionEvent) {
// TODO Auto-generated method stub
autocomptv.showDropDown();
autocomptv.requestFocus();
return false;
}
});
您需要执行这些步骤才能使其完美运行
1-在你的 xml 中放入这个
<androidx.appcompat.widget.AppCompatAutoCompleteTextView
android:id="@+id/account_type_spinner"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="@dimen/_16sdp"
android:layout_marginTop="@dimen/_24sdp"
android:layout_marginEnd="@dimen/_16sdp"
android:background="@drawable/rounded_edt_with_border"
android:completionThreshold="0"
android:drawableRight="@drawable/ic_arrow_down"
android:hint="@string/account_type"
android:imeOptions="actionNext"
android:inputType="text"
android:padding="12dp"
android:textSize="@dimen/_15sp"
/>
您只需将
android:completionThreshold2- 在你的java代码中放入
mViewDataBinding.accountTypeSpinner.setOnFocusChangeListener((v, hasFocus) -> {
if (hasFocus)
mViewDataBinding.accountTypeSpinner.showDropDown();
});
用这个：
text.setOnTouchListener(new View.OnTouchListener(){
@Override
public boolean onTouch(View arg0, MotionEvent arg1) {
// TODO Auto-generated method stub
text.showDropDown();
return false;
}
});
Nothing Custom Required.
我尝试了所有解决方案，但在某些情况下不起作用。例如 一个解决方案第一次有效，但当您删除文本时，它不会 出现。所以我进行了更多挖掘并找到了以下解决方案。
欢迎提出建议。
XML：
<android.support.design.widget.TextInputLayout
android:id="@+id/tl"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<android.support.v7.widget.AppCompatAutoCompleteTextView
android:id="@+id/autoComplete"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="Hint Here" />
</android.support.design.widget.TextInputLayout>
科特林：
val adapter = ArrayAdapter<BusinessNoResult>(context, android.R.layout.select_dialog_item, listItems)
autoComplete.setAdapter(adapter)
//threshold specifies the minimum number of characters the user has to type in
//the
//edit box before the drop down list is shown
autoComplete.threshold = 0
//we have to add check for 0 number of character in edit text. When that
//happens, we will show pop up manually
autoComplete.addTextChangedListener(object : TextWatcher {
override fun afterTextChanged(s: Editable?) {}
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {}
override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
//first check if length of input is 0
if(s?.length ?: 0 == 0){
//if you don't use handler with post delay, the API will hide pop
//up, even if you show it. There could be better ways to this, but
//I have implemented this and after 100 millis it gives an animated
//look
Handler().postDelayed({
//manually show drop down
autoComplete.showDropDown()
}, 100) // with 100 millis of delay
}
}
})
//when user focus out the view, drop down vanishes. When come back it will not
//show, so to cover this scenario add following.
autoComplete.setOnFocusChangeListener { _, hasFocus ->
//when gain focus manually show drop down
if(hasFocus)
autoComplete.showDropDown()
}
所有答案都已过时。通过材料设计，它变得更加容易和流畅。确保将 inputType 设置为 none，这样就不再打开键盘了。
XML
<com.google.android.material.textfield.TextInputLayout
android:id="@+id/et_countries_list"
style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox.ExposedDropdownMenu"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="20dp"
android:hint="Demo hint"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintTop_toTopOf="parent"
>
<com.google.android.material.textfield.MaterialAutoCompleteTextView
android:id="@+id/countries_list"
android:layout_width="match_parent"
android:inputType="none"
android:layout_height="60dp"
/>
</com.google.android.material.textfield.TextInputLayout>
然后只需添加准备好适配器并添加即可。
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_dropdown_item_1line, new String[]{
"Belgium", "France", "Italy", "Germany", "Spain", "Belgium", "France", "Italy", "Germany", "Spain"});
AutoCompleteTextView autoCompleteTextView = (AutoCompleteTextView)
findViewById(R.id.countries_list);
autoCompleteTextView.setAdapter(adapter);
你已经完成了。它比旋转器效果更好。您还可以设置提示、错误、帮助程序。
如果其他解决方案对您不起作用，请尝试此解决方案。点击时始终显示弹出窗口。
public class InstantAutoComplete extends AppCompatAutoCompleteTextView {
public InstantAutoComplete(Context context) {
super(context);
}
public InstantAutoComplete(Context arg0, AttributeSet arg1) {
super(arg0, arg1);
}
public InstantAutoComplete(Context arg0, AttributeSet arg1, int arg2) {
super(arg0, arg1, arg2);
}
@Override
public boolean enoughToFilter() {
return true;
}
@Override
public boolean onTouchEvent(MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
performClick();
}
return super.onTouchEvent(event);
}
@Override
public boolean performClick() {
if (getFilter() != null && !isPopupShowing()) {
performFiltering(getText(), 0);
showDropDown();
}
return super.performClick();
}
}
这里使用 onclicklistener 的方法，因为我发现 onTouch 在尝试滚动时有点令人恼火。 mOccupation 是有问题的 AutocompleteTextView。
mOccupation=(AutoCompleteTextView) findViewById(R.id.actv_occupation);
ArrayAdapter<String> occupationAdapter=new ArrayAdapter<String>
(NewClientActivity.this,
android.R.layout.simple_list_item_1,
getResources().getStringArray(R.array.occupation_array));
mOccupation.setAdapter(occupationAdapter);
mOccupation.setKeyListener(null);
mOccupation.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//mOccupation.setText(null);
((AutoCompleteTextView) view).showDropDown();
return;
}
});
我设法将其全部放入具有以下 xml 规范的 Textinputlayout 中：
<android.support.design.widget.TextInputLayout
android:id="@+id/lo_occupation"
android:layout_marginTop="10dp"
android:layout_gravity="center_horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<AutoCompleteTextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="occupation"
android:focusableInTouchMode="false"<--this is the important part
android:id="@+id/actv_occupation"
android:ems="10"
android:completionThreshold="0"<--this too
/>
</android.support.design.widget.TextInputLayout>
它帮助了我：
private AutoCompleteTextView autoCompleteTextViewRFID;
...
autoCompleteTextViewRFID = binding.choiceFieldRFID;
List<String> rfidArray = databaseManager.readCowsRFID();
ArrayAdapter<String> rfidAdapter = new ArrayAdapter<>(getActivity(), android.R.layout.simple_dropdown_item_1line, rfidArray);
autoCompleteTextViewRFID.setThreshold(1);
autoCompleteTextViewRFID.setAdapter(rfidAdapter);
...
autoCompleteTextViewTypeRange.setOnTouchListener((v, event) -> {
autoCompleteTextViewTypeRange.showDropDown();
return true;
});
XML：
<AutoCompleteTextView
android:id="@+id/typeRange"
android:gravity="center"
android:focusable="true"
android:focusableInTouchMode="true"
android:layout_width="match_parent"
android:layout_height="40dp" />
我对此有一个很好的解决方案。这很简单。这只是下拉菜单并从选项中进行选择。
确保将这两行添加到 XML 中。
android:completionThreshold="0"android:focusableInTouchMode="false"XML
<com.google.android.material.textfield.TextInputLayout
android:layout_marginTop="10dp"
style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<androidx.appcompat.widget.AppCompatAutoCompleteTextView
android:id="@+id/select_area"
android:layout_width="match_parent"
android:layout_height="52dp"
android:padding="10dp"
android:textSize="15sp"
android:singleLine="true"
android:drawableEnd="@drawable/ic_arrow_down"
android:completionThreshold="0"
android:focusableInTouchMode="false"
android:hint="Select an Area"
android:inputType="text"
android:maxLines="1" />
</com.google.android.material.textfield.TextInputLayout>
JAVA
area_autocomplete.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
area.showDropDown();
}
});
您可以简单地使用这一行代码
autoCompleteTextView.setThreshold(100);