如何使用单个onClickListener

Question

我有80个按钮，用户必须能够通过长按事件重命名并保存新的按钮文本。当用户关闭应用程序时，它必须保持相同的文本，并且不能返回默认文本。这就是我对第一个按钮的看法。我将如何做到这一点，以便它知道长按哪个按钮并重命名。（这个编码在我外出时不会保存它）

public class MainActivity extends AppCompatActivity {

private Button btn1 , btn2 , btn3 , btn4 ;

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

    View.OnLongClickListener listener = new View.OnLongClickListener() {
        @Override
        public boolean onLongClick(View v) {
            showPopup(v);
            return true;    //Nothing shows error, but this part where i tried to set a onLongClick listener. 
        }
    };

    btn1.setOnLongClickListener(listener);
    btn2.setOnLongClickListener(listener);
    btn3.setOnLongClickListener(listener);
    btn4.setOnLongClickListener(listener);

    SharedPreferences prefs = getSharedPreferences("btnID", Context.MODE_PRIVATE);
    Map<String,?> keys = prefs.getAll();
    for(Map.Entry<String,?> entry : keys.entrySet()){
        Button button = (Button) findViewById(Integer.parseInt(entry.getKey()));
        button.setText(entry.getValue().toString());
    }

}


private void showPopup(View v) {
    //here you have your button
    final Button currentButton = (Button)v;
    v.setOnLongClickListener(new View.OnLongClickListener() {
        @Override
        public boolean onLongClick(View v) {
            showPopup(v);
            return true;
        }
    });


    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("Rename to?");
    View view = LayoutInflater.from(this).inflate(R.layout.dialog_view, null);
    final EditText edit_dialog = (EditText)view.findViewById(R.id.edit_dialog);

    edit_dialog.setText(currentButton.getText().toString());
    builder.setView(view);
    builder.setPositiveButton("confirm", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            currentButton.setText(edit_dialog.getText().toString());
            SharedPreferences prefs = getSharedPreferences("btnID", Context.MODE_PRIVATE);
            SharedPreferences.Editor editor = prefs.edit();
            editor.putString(String.valueOf(currentButton.getId()), currentButton.getText().toString());
            editor.apply();
        }


    });
    builder.show();
}

}

Answer 1

您还必须传递按钮的ID，例如：

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

    btn1 = (Button) findViewById(R.id.btn1);
    btn2 = (Button) findViewById(R.id.btn2);
    btn3 = (Button) findViewById(R.id.btn3);
    btn4 = (Button) findViewById(R.id.btn4);

    //HERE you load the button texts from SharedPrefs or SQLite and you set the text to the buttons from ids

    btn1.setOnLongClickListener(new View.OnLongClickListener() {
        @Override
        public boolean onLongClick(View v) {
                showDialog("", v.getId());
            return true;
        }
    });


}

private void showDialog(String str, int btnId) {
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("Rename to?");
    View view = LayoutInflater.from(this).inflate(R.layout.dialog_view, null);
    final EditText edit_dialog = (EditText) view.findViewById(R.id.edit_dialog);
    edit_dialog.setText(str);
    builder.setView(view);
    builder.setPositiveButton("confirm", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            btn1.setText(edit_dialog.getText().toString());
            //HERE you save the text and the relative id.
            //you can use both SharedPrefs or SQLite
        }
    });
    builder.show();
}

检查注释以查看何时保存/加载数据

如何使用单个onClickListener

您必须自定义onClick方式以检索单击按钮的ID。您可以保存在sharedPreferences

中

private void showDialog(View v) {
    //here you have your button
    Button currentButton = (Button)v;

    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("Rename to?");
    View view = LayoutInflater.from(this).inflate(R.layout.dialog_view, null);
    final EditText edit_dialog = (EditText)view.findViewById(R.id.edit_dialog);

    edit_dialog.setText(currentButton.getText().toString());
    builder.setView(view);
    builder.setPositiveButton("confirm", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            currentButton.setText(edit_dialog.getText().toString());
            SharedPreferences prefs = this.getSharedPreferences("sharedPrefName", Context.MODE_PRIVATE);
            SharedPreferences.Editor editor = prefs.edit();
            editor.putString(String.valueOf(currentButton.getId), currentButton.getText().toString());
            editor.apply();
        }
    });
    builder.show();
}

你可以在xml中使用onclick调用这个方法：

<Button
  android:id="@+id\myId"
  android:layout-width="wrap-content"
  android:layout-height="wrap-content"
  android:onclick="showDialog"
  />

通过这种方式，您可以为每个按钮使用单一方法。

PS：

你必须在onCreate中添加一些内容来实现按钮的初始化：

SharedPreferences prefs = this.getSharedPreferences("sharedPrefName", Context.MODE_PRIVATE);
Map<String,?> keys = prefs.getAll();
for(Map.Entry<String,?> entry : keys.entrySet()){
  Button button = findViewById(Integer.Parse(entry.getHey()));
  button.setText(entry.getValue().toString());
}

很抱歉，如果它有任何错误，但我手写了，所以我没有编译器。

希望这有帮助

Answer 2

我也遇到了与@Bernard相同的问题。然后我做了一些研究并将所有ID的按钮存储在一个数组中。我刚刚对@Pier Giorgio Misley给出的解决方案做了一些修改。非常感谢Misley的帮助。我可以用你的解决方案来解决这个问题。

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

    buttons = new ArrayList<Button>(BUTTON_IDS.length);

    SharedPreferences prefs = getSharedPreferences("btnID", Context.MODE_PRIVATE);
    Map<String,?> keys = prefs.getAll();
    for(Map.Entry<String,?> entry : keys.entrySet()){
        Button button = (Button) findViewById(Integer.parseInt(entry.getKey()));
        button.setText(entry.getValue().toString());
    }

    for(int id : BUTTON_IDS) {
        Button button = (Button)findViewById(id);
        button.setOnLongClickListener(new View.OnLongClickListener() {
            @Override
            public boolean onLongClick(View v) {
                renameButton("",v);
                return true;
            }
        });

    }
}

private void renameButton(String str,View v) {
    final Button currentButton = (Button)v;
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("Rename to?");
    View view = LayoutInflater.from(this).inflate(R.layout.dialog_view, null);
    final EditText edit_dialog = (EditText)view.findViewById(R.id.edit_text);

    edit_dialog.setText(str);
    builder.setView(view);
    builder.setPositiveButton("confirm", new DialogInterface.OnClickListener() {

        @Override
        public void onClick(DialogInterface dialog, int which) {
            currentButton.setText(edit_dialog.getText().toString());
            SharedPreferences prefs = getSharedPreferences("btnID", Context.MODE_PRIVATE);
            SharedPreferences.Editor editor = prefs.edit();
            editor.putString(String.valueOf(currentButton.getId()), currentButton.getText().toString());
            editor.apply();
        }
    });
    builder.show();
}

在onCreate方法

上创建一个按钮ID数组

     private List<Button> buttons;
private static final int[] BUTTON_IDS = {
        R.id.btn1,
        R.id.btn2,
        R.id.btn3,
        R.id.btn4,
};

让用户在longclick事件上重命名按钮并保存

2 个答案:

如何使用单个onClickListener