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java Android SDK在发布时挂起设备

大家好,我是初学者,我想编写简单的点击事件,所以我在Android SDK和Eclipse中编写了以下代码:

package com.example.aplic;

import 安卓.support.v7.app.ActionBarActivity;
import 安卓.support.v4.app.Fragment;
import 安卓.os.Bundle;
import 安卓.view.LayoutInflater;
import 安卓.view.Menu;
import 安卓.view.MenuItem;
import 安卓.view.View;
import 安卓.view.View.OnClickListener;
import 安卓.view.ViewGroup;
import 安卓.widget.Button;
import 安卓.widget.TextView;

public class MainActivity extends ActionBarActivity {

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

        Button b = (Button) findViewById(R.id.button1);

        b.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                TextView tx = (TextView) findViewById(R.id.textView1);
                tx.setText("yourtext");
            }
         });

        if (savedInstanceState == null) {
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.container, new PlaceholderFragment())
                    .commit();
        }

    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    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 == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_main, container, false);
            return rootView;
        }
    }

}

以及:

<RelativeLayout xmlns:安卓="http://schemas.安卓.com/apk/res/安卓"
    xmlns:tools="http://schemas.安卓.com/tools"
    安卓:layout_width="match_parent"
    安卓:layout_height="match_parent"
    安卓:paddingBottom="@dimen/activity_vertical_margin"
    安卓:paddingLeft="@dimen/activity_horizontal_margin"
    安卓:paddingRight="@dimen/activity_horizontal_margin"
    安卓:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.aplic.MainActivity$PlaceholderFragment" >

    <TextView
        安卓:id="@+id/textView1"
        安卓:layout_width="wrap_content"
        安卓:layout_height="wrap_content"
        安卓:text="@string/hello_world" />

    <Button
        安卓:id="@+id/button1"
        安卓:layout_width="wrap_content"
        安卓:layout_height="wrap_content"
        安卓:layout_below="@+id/textView1"
        安卓:layout_marginTop="110dp"
        安卓:layout_toRightOf="@+id/textView1" />

    <ImageView
        安卓:id="@+id/imageView1"
        安卓:layout_width="wrap_content"
        安卓:layout_height="wrap_content"
        安卓:layout_alignLeft="@+id/button1"
        安卓:layout_below="@+id/button1"
        安卓:layout_marginTop="96dp"
        安卓:contentDescription="@string/abc_action_mode_done"
        安卓:src="@drawable/abc_ab_bottom_solid_dark_holo" />

</RelativeLayout>

问题是,当我在模拟器上启动代码时,它会挂起并重置,当我在真实设备上启动代码时,它会关闭程序,我不知道它出了什么问题,我是否使用了错误的事件

PS:当我删除onclick事件部分时,它工作正常,但不会在单击时做出反应

主要活动。xml:

<FrameLayout xmlns:安卓="http://schemas.安卓.com/apk/res/安卓"
    xmlns:tools="http://schemas.安卓.com/tools"
    安卓:id="@+id/container"
    安卓:layout_width="match_parent"
    安卓:layout_height="match_parent"
    tools:context="com.example.deomanapp.MainActivity"
    tools:ignore="MergeRootFrame" />

共 (1) 个答案

  1. # 1 楼答案

    该按钮似乎属于fragment_main.xml

    根据你的评论

    The name is fragment_main.xml

    它不是挂着的。这是一次撞车。你可能会得到NullPointerException

    改为

      @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
           final View rootView = inflater.inflate(R.layout.fragment_main, container, false);
            Button b = (Button) rootView.findViewById(R.id.button1);
    
            b.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                TextView tx = (TextView) rootview.findViewById(R.id.textView1);
                tx.setText("yourtext");
            }
         });
            return rootView;
        }