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java android处理程序调用_Java_Android - Fatal编程技术网

java android处理程序调用

java android处理程序调用,java,android,Java,Android,我是android编程新手。我看到了许多处理事件的方法,但当我试图通过调用处理程序类来处理事件时,它会在处理类名时出错: package com.example.test; import android.app.Activity; import android.content.DialogInterface.OnClickListener; import android.os.Bundle; import android.view.View; import android.widget.But

我是android编程新手。我看到了许多处理事件的方法,但当我试图通过调用处理程序类来处理事件时,它会在处理类名时出错:

package com.example.test;

import android.app.Activity;
import android.content.DialogInterface.OnClickListener;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        //attach an instance of HandleClick to the Button
        findViewById(R.id.button1).setOnClickListener(new HandleClick());
    }    

    private class HandleClick implements OnClickListener{
        public void onClick(View arg0) {
            Button btn = (Button)arg0;  //cast view to a button
            // get a reference to the TextView
            TextView tv = (TextView) findViewById(R.id.textview1);
            // update the TextView text
            tv.setText("You pressed " + btn.getText());
        }
    }
}
“HandleClick”
出现错误,它说类应该是抽象类型吗


我不明白为什么会出现这个错误,有人能帮我吗?

那是错误的OnClickListener类。你有

 import android.content.DialogInterface.OnClickListener;
你需要:

 import android.view.View.OnClickListener;

为了将来参考,您得到的错误是“类型必须实现继承的抽象方法…”。这是因为您需要实现DialogInterface的onClick,这应该会让您注意到它是错误的导入(因为您有
onClick(View)

简化并使用它

b1 = (Button) findViewById(R.id.button1);
TextView tv = (TextView) findViewById(R.id.textview1);
b1.setOnClickListener(new OnClickListener()
{
    public void onClick(View v)
    {
        Toast msg = Toast.makeText(getBaseContext(),
        "You have clicked Button 1", Toast.LENGTH_LONG);
        msg.show();
        tv.setText("You pressed " + btn.getText());
    }
});

您导入了错误的OnClickListener,您应该从android.view.view导入一个