Question

问题是获取所选项目包含的内容，但我尝试了很多代码和解决方案仍然无法正常工作。有人看到了问题吗？

final List list = db.getAllClients();

    final ListView listview = (ListView) findViewById(R.id.listView_ID);
    listview.setClickable(true);

    final ArrayAdapter adapter = new ArrayAdapter(this,
            android.R.layout.simple_list_item_1, list);

    listview.setAdapter(adapter);
    registerForContextMenu(listview);

    listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {

            String selectedText = (String) listview
                    .getItemAtPosition(position);

            Toast.makeText(getApplicationContext(), selectedText,
                    Toast.LENGTH_SHORT);
        }
    });

堆栈跟踪：

01-15 04：37：43.058：I / Choreographer（2137）：跳过137帧！应用程序可能在其主线程上做了太多工作。 01-15 04：37：44.998：I / Choreographer（2137）：跳过40帧！应用程序可能在其主线程上做了太多工作。

01-15 04:37:46.358: W/dalvikvm(2137): threadid=1: thread exiting with uncaught exception (group=0xb3aa9b90)
01-15 04:37:46.418: E/AndroidRuntime(2137): FATAL EXCEPTION: main
01-15 04:37:46.418: E/AndroidRuntime(2137): Process: com.example.assist, PID: 2137
01-15 04:37:46.418: E/AndroidRuntime(2137): java.lang.ClassCastException: com.example.assist.Client cannot be cast to java.lang.String
01-15 04:37:46.418: E/AndroidRuntime(2137):     at com.example.assist.ListActivity$1.onItemClick(ListActivity.java:68)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at android.widget.AdapterView.performItemClick(AdapterView.java:299)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at android.widget.AbsListView.performItemClick(AbsListView.java:1113)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at android.widget.AbsListView$PerformClick.run(AbsListView.java:2904)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at android.widget.AbsListView$3.run(AbsListView.java:3638)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at android.os.Handler.handleCallback(Handler.java:733)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at android.os.Handler.dispatchMessage(Handler.java:95)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at android.os.Looper.loop(Looper.java:137)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at android.app.ActivityThread.main(ActivityThread.java:4998)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at java.lang.reflect.Method.invokeNative(Native Method)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at java.lang.reflect.Method.invoke(Method.java:515)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593)
01-15 04:37:46.418: E/AndroidRuntime(2137):     at dalvik.system.NativeStart.main(Native Method)
01-15 04:42:46.598: I/Process(2137): Sending signal. PID: 2137 SIG: 9

Answer 1

替换它：

Toast.makeText(getApplicationContext(), selectedText,
                Toast.LENGTH_SHORT);

以下：

Toast.makeText(getApplicationContext(), selectedText,
                Toast.LENGTH_SHORT).show();

你忘了在Toast中.show()。就是这样。

Answer 2

您错过了.show()

Toast.makeText(getApplicationContext(), selectedText,
                Toast.LENGTH_SHORT).show();

Answer 3

数组适配器的列表为Client而非String。要获取列表视图中显示的字符串，请更改此

String selectedText = (String) listview
                .getItemAtPosition(position);

类似

String selectedText = ((Client) listview
                .getItemAtPosition(position)).toString();

并将.show()添加到吐司中，如其他答案中已提到的那样。

Android系统。显示单击的项目文本。为什么不起作用？

3 个答案: