Question

我向Toolbar添加了Activity，并带有后退箭头，如下所示：

Toolbar myToolbar = (Toolbar) findViewById(R.id.my_toolbar);        
setSupportActionBar(myToolbar);
//add back arrow - but it doesn't go back, nothing happens when I click it
getSupportActionBar().setDisplayHomeAsUpEnabled(true);

但是当我单击后退箭头时，它不会返回上一页

Answer 1

添加以下行：

@Override
public boolean onSupportNavigateUp() {
    onBackPressed();
    return true;
}

@Override
public void onBackPressed() {
    super.onBackPressed();
    finish(); // or your code
}

Answer 2

您需要像这样覆盖onCreateOptionsMenu()和onOptionsItemSelected()：

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.your_id, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case android.R.id.home:
            onBackPressed();
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

别忘了用您的ID代替R.menu.your_id作为名称建议。

Answer 3

根据建议的答案，您可能希望在Android manifest.xml中添加parentActivity

<application ... >
...
<!-- The main/home activity (it has no parent activity) -->
<activity
    android:name="com.example.myfirstapp.MainActivity" ...>
    ...
</activity>
<!-- A child of the main activity -->
<activity
    android:name="com.example.myfirstapp.DisplayMessageActivity"
    android:label="@string/title_activity_display_message"
    android:parentActivityName="com.example.myfirstapp.MainActivity" >
    <!-- The meta-data element is needed for versions lower than 4.1 -->
    <meta-data
        android:name="android.support.PARENT_ACTIVITY"
        android:value="com.example.myfirstapp.MainActivity" />
</activity>

文档：Android developers

为什么工具栏的后退按钮不起作用？

3 个答案: