为什么onBack pressed（）不会被调用？ [英] Why is onBackPressed() not being called?

问题描述

我试图重写onBack pressed（）。然而，它出现时我点击操作栏中的后退按钮无法察觉。

I am attempting to override onBackPressed(). However it appears to not detect when I click the back button in the action bar.

目前，我有这个code：

I currently have this code:

@Override
public void onBackPressed()  {

    Log.i("DATA", "Hit onBackPressed()");
    super.onBackPressed();

}

日志信息不会出现在LogCat中。我知道，这个日志语句的工作，因为它是从，它在LogCat中显示不同的信息的另一种方法复制。

The log message never appears in the LogCat. I know that this log statement works because it is copied from another method with a different message that DOES display in the LogCat.

我已经寻找答案，我一直在使用onKeyDown和检测它是否被点击返回按钮，但我仍然有同样的问题尝试。
关于该项目的信息：

I have searched for answers, and I have tried using onKeyDown and detecting if it is the BACK button being clicked but I still have the same issue. Information about the project:

• Android的工作室0.9.3


• 方法位于空白活动


• 目标SDK 21


• 最小SDK 15


• 测试设备是三星Galaxy 5（而不是仿真器）

任何帮助将大大AP preciated !!

Any help would be greatly appreciated!!

编辑：

这是我的工作code的副本（这是测试code这样的活动名称不是描述性的）：

This is a copy of my working code (this is test code so the activity name is not descriptive):

public class MainActivity2 extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main_activity2);
    getActionBar().setDisplayHomeAsUpEnabled(true);//Displays the back button
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_main_activity2, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case android.R.id.home:

            Log.i("DATA", "Hit Actionbar Back Button");

            return true;

        default:
            return super.onOptionsItemSelected(item);
    }
}

}

消息打动作条后退按钮现在出现在LogCat中。

The message "Hit Actionbar Back Button" now appears in the LogCat.

推荐答案

onBack pressed（）当用户点击一个硬件后退按钮被调用（或向上导航栏中的按钮），而不是在动作栏按钮。对于这一项，你需要重写 onOptionsItemSelected（）方法。例如：

onBackPressed() is invoked when user clicks on a hardware back button (or on the 'up' button in the navigation bar), not the button in the action bar. For this one you need to override onOptionsItemSelected() method. Example:

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case android.R.id.home:
            // click on 'up' button in the action bar, handle it here
            return true;

        default:
            return super.onOptionsItemSelected(item);
    }
}    

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