Question

您好我试图让3个单选按钮更改onclick侦听器的按钮，每个单选按钮在该按钮的单击侦听器上设置自己的按钮。但我明白了（MainActivity不是封闭类）

注意：radiobuttons处于设置活动状态，按钮处于主要活动状态。

设置

public class Settings extends MainActivity {

private RadioGroup radioGroup;
private RadioButton radioButtonpc;
private RadioButton radioButtonps;
private RadioButton radioButtonxb;
public Button settings;
public Button cheatsactivity;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.settings);

    cheatsactivity = (Button) findViewById(R.id.cheats_activity);
    settings = (Button) findViewById(R.id.setting_btn);
    radioGroup = (RadioGroup) findViewById(R.id.RadioGroup);
    radioButtonpc = (RadioButton) findViewById(R.id.radioButton1);
    radioButtonxb = (RadioButton) findViewById(R.id.radioButton2);
    radioButtonps = (RadioButton) findViewById(R.id.radioButton3);

    radioButtonpc.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            cheatsactivity.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Intent intent = new Intent(MainActivity.this, PC.class);
                    startActivity(intent);
                }
            });
        }
    });

    radioButtonxb.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            cheatsactivity.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Intent intent = new Intent(MainActivity.this, XBOX.class);
                    startActivity(intent);
                }
            });
        }
    });
    radioButtonps.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            cheatsactivity.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Intent intent = new Intent(MainActivity.this, PS.class);
                    startActivity(intent);
                }
            });
        }
    });
}




}

更新它现在给了我 java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference whenever i clicked on the radio button 我试图改变，让用户从设置活动的任何解决方案中更改主要活动按钮的onclick监听器？

Answer 1

您需要使用生活活动上下文作为new Intent的第一个参数。

尝试在您的意图中将MainActivity.this更改为Settings.this，例如

Intent intent = new Intent(Settings.this, PC.class);

Answer 2

写Settings.this代替MainActivity.this，如@howdoidothis所说。我认为你错误地使用了onClickListener而不是onCheckChangedListener。请参阅以下示例：

rd.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener()
{
    @Override
    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked)
    {
        Intent intent = new Intent(Settings.this, PC.class);
        startActivity(intent);
    }
});

Answer 3

首先，始终遵循可重用性，因为您使用了Radio组，并通过单击另一个按钮从单选按钮应用意图。

一旦使用下面的代码段，如果仍然无效，请在此处更新，

radioGroup 
        .setOnCheckedChangeListener(new OnCheckedChangeListener() {

            @Override
            public void onCheckedChanged(RadioGroup group, int checkedId) {
            Log.d("chk", "id" + checkedId);

                if (checkedId == R.id.radioButton1) {
                    //some code
                     Intent intent = new Intent(Settings .this, PC.class);
                    startActivity(intent);
                } else if (checkedId == R.id.radioButton2) {
                    //some code
                     Intent intent = new Intent(Settings .this, XBOX.class);
                    startActivity(intent);

                }else if (checkedId == R.id.radioButton3) {
                    //some code
                      Intent intent = new Intent(Settings .this, PS.class);
                    startActivity(intent);
                }

            }

        });

Answer 4

试用此代码

radioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
                    @Override
                    public void onCheckedChanged(RadioGroup radioGroup, int i) {
                        if (i == radioButtonpc.getId()) {
                            //your code
                        }
                        if (i == radioButtonxx.getId()) {
                            //your code
                        }
                        if (i == radioButton.getId()) {
                            //your code
                        }
                        if (i == radioButtonab.getId()) {
                            //your code
                        }
                    }
                });

从单选按钮更改onclicklistener以获取按钮

4 个答案: