Question

使用标准或支持ActionMode，下面链接的问题中的过程对我来说似乎不起作用。 ACTION_UP永远不会作为参数出现，虽然ACTION_DOWN可以，但无论如何，ActionMode仍然被取消。

Prevent to cancel Action Mode by press back button

有人建议如何在按下后退键时阻止动作模式关闭吗？

我的代码

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;

import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class test extends AppCompatActivity  {

Toolbar toolbar;
Button standard;
Button support;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.test);

    toolbar= (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    standard= (Button) findViewById(R.id.standard);
    standard.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            startActionMode(standardCallback);
            standard.setVisibility(View.GONE);
            support.setVisibility(View.GONE);
        }
    });

    support= (Button) findViewById(R.id.support);
    support.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            startSupportActionMode(supportCallback);
            standard.setVisibility(View.GONE);
            support.setVisibility(View.GONE);
        }
    });

}

private android.view.ActionMode.Callback standardCallback=new android.view.ActionMode.Callback() {
    @Override
    public boolean onCreateActionMode(android.view.ActionMode mode, Menu menu) {
        mode.setTitle("Standard Action Mode Enabled");
        return true;
    }

    @Override
    public boolean onPrepareActionMode(android.view.ActionMode mode, Menu menu) {
        return false;
    }

    @Override
    public boolean onActionItemClicked(android.view.ActionMode mode, MenuItem item) {
        return false;
    }

    @Override
    public void onDestroyActionMode(android.view.ActionMode mode) {
        standard.setVisibility(View.VISIBLE);
        support.setVisibility(View.VISIBLE);
    }
};

//requires theme entry: <item name="windowActionModeOverlay">true</item>
private android.support.v7.view.ActionMode.Callback supportCallback=new android.support.v7.view.ActionMode.Callback() {
    @Override
    public boolean onCreateActionMode(android.support.v7.view.ActionMode mode, Menu menu) {
        mode.setTitle("Support Action Mode Enabled");
        return true;
    }

    @Override
    public boolean onPrepareActionMode(android.support.v7.view.ActionMode mode, Menu menu) {
        return false;
    }

    @Override
    public boolean onActionItemClicked(android.support.v7.view.ActionMode mode, MenuItem item) {
        return false;
    }

    @Override
    public void onDestroyActionMode(android.support.v7.view.ActionMode mode) {
        standard.setVisibility(View.VISIBLE);
        support.setVisibility(View.VISIBLE);
    }
};

@Override
public boolean dispatchKeyEvent(KeyEvent event) {
        if (event.getKeyCode() == KeyEvent.KEYCODE_BACK && event.getAction() == KeyEvent.ACTION_UP) {
            // handle your back button code here
            Toast.makeText(this,"Back ACTION_UP",Toast.LENGTH_LONG).show();
            return true; // consumes the back key event - ActionMode is not finished
        }

    if (event.getKeyCode() == KeyEvent.KEYCODE_BACK && event.getAction() == KeyEvent.ACTION_DOWN) {
        // handle your back button code here
        Toast.makeText(this,"Back ACTION_DOWN",Toast.LENGTH_LONG).show();
        return true; // consumes the back key event - ActionMode is not finished
    }

    return super.dispatchKeyEvent(event);
}

}

布局

<?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">

<android.support.v7.widget.Toolbar
    android:id="@+id/toolbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="?attr/colorPrimary"
    android:minHeight="?android:attr/actionBarSize"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"/>

<Button
    android:id="@+id/standard"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_margin="30dp"
    android:text="Standard"/>

<Button
    android:id="@+id/support"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_margin="30dp"
    android:text="Support"/>

</LinearLayout>

Answer 1

我通过使用支持库中的工具栏来模拟ActionMode栏来解决这个问题。

Answer 2

我遇到了这个问题，并通过将AppCompatActivity更改为Activity来解决了这个问题。我不知道为什么，但是在AppCompatActivity中，当actionMode工作时，它不会读取KeyEvent.ACTION_UP。但是在Activity中确实如此。

在ActionMode处于活动状态时阻止后退按钮

2 个答案: