Question

我正在开发一个Android应用程序。在此应用程序中，我有3个活动1作为标题活动，另一个作为字幕活动，另一个是详细活动

现在我想向上导航从一个活动（字幕活动）到父活动（标题活动 ）通过使用以下代码，我执行该操作

SubTitleActivity：

   protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.subcategory_activity);
    actionBar=getSupportActionBar();
listView2= (ListView) findViewById(R.id.listView2);
Intent intent= getIntent();
final String selectedData = intent.getStringExtra("selectedItem");
actionBar.setTitle(selectedData);
dbHelper = new SqlLiteDbHelper(this);
try {
    dbHelper.openDataBase();
} catch (SQLException e) {
    e.printStackTrace();
}

sqLiteDatabase=dbHelper.getReadableDatabase();
cursor=dbHelper.getsubcategory(sqLiteDatabase,selectedData);
String[] from = new String[] { dbHelper.SUBCATEGORY };
int[] to = new int[] {R.id.subcategory };
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,R.layout.subcategory_row,cursor,from,to);
adapter.notifyDataSetChanged();
listView2.setAdapter(adapter);
listView2.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        Cursor cursor = (Cursor) (listView2.getItemAtPosition(position));
        String selectedItem = cursor.getString(0);
        Intent intent = new Intent(SubcategoryActivity.this, DetailActivity.class);
        intent.putExtra("selectedItem", selectedItem);
        startActivity(intent);
    }
});


        public boolean onOptionsItemSelected(MenuItem item) {
                // Handle action bar item clicks here. The action bar will
                // automatically handle clicks on the Home/Up button, so long
                // as you specify a parent activity in AndroidManifest.xml.
                int id = item.getItemId();

                if (id==android.R.id.home)
                {
                    NavUtils.navigateUpFromSameTask(this);
                }
                return super.onOptionsItemSelected(item);
            }
        }

的Manifest.xml

<activity
            android:name=".SubcategoryActivity"
            android:label="@string/title_activity_subcategory" >
            <meta-data android:name="android.support.PARENT_ACTIVITY" android:value=".MainActivity"></meta-data>
        </activity>

现在我不知道如何从我的细节活动转移到子活动，我们怎么能执行呢？

DetailActivity：

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.detail_activity);
    actionBar=getSupportActionBar();
detailtext= (TextView) findViewById(R.id.detail);
imageView= (ImageView) findViewById(R.id.images);

getSupportActionBar().setHomeButtonEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);


Intent intent= getIntent();
final String selectedData = intent.getStringExtra("selectedItem");
actionBar.setTitle(selectedData);
dbHelper = new SqlLiteDbHelper(this);
try {
    dbHelper.openDataBase();
} catch (SQLException e) {
    e.printStackTrace();
}

sqLiteDatabase = dbHelper.getReadableDatabase();
cursor=dbHelper.getdetails(sqLiteDatabase, selectedData);
if(cursor.moveToFirst())
{
    detailtext.setText(cursor.getString(0));
}
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    if (id==android.R.id.home)
    {

        onBackPressed();

    }

Answer 1

在DetailsActivity代码中执行以下操作：

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

有关Tasks and Back Stack（特别是Using Intent Flags部分）的更多信息，请访问：http://developer.android.com/guide/components/tasks-and-back-stack.html

Answer 2

使用

Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
toolbar.setNavigationOnClickListener(View.OnClickListener);

并点击监听器，如：

new View.OnClickListener() {
            @Override
            public void onClick(View view) {
               YourActivity.this.onBackPressed();
            }

如何使用Intent将Navigateup从第三个活动返回到第二个活动

2 个答案: