Question

获取Android FATAL EXCEPTION以下代码中的主要错误不知道为什么会发生这种情况。??有一个plz为我解释，plz plz帮助我自己发现错误 ...... !!

主要活动类： -

package www.gurjit.taskmanager;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {

    private Button add_button;
    private View tasklist_view;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        setUpElements(); // for setting up all the views/elements of the android page.
    }

    private void setUpElements() {
        add_button = (Button)findViewById(R.id.addButton);
        tasklist_view = findViewById(R.id.textView2);
        add_button.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View arg0) {
                Intent in = new Intent(MainActivity.this, addActivityTask.class);
                startActivity(in);
            }
        });
    }

    @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;
    }

}

这是我的Android_Main布局文件＆amp;不知道如何发生此错误虽然按照相同的方式使用（Google API 4.3）Api级别： -

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/tasks"
        android:textColor="#12ade4"
        android:textSize="20sp" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:textColor="#12ade4"
        android:textSize="20sp"
        android:layout_above="@+id/addButton"
        android:layout_below="@id/textView1" />

    <button
        android:id="@id/addButton"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/add_button"
        android:textSize="15sp" 
        android:padding="10dp"
        android:layout_alignParentBottom="true"/>

</RelativeLayout>

下面是出现的logcat文件： -

01-28 09:12:45.150: D/AndroidRuntime(1766): Shutting down VM
01-28 09:12:45.150: W/dalvikvm(1766): threadid=1: thread exiting with uncaught exception (group=0x41465700)
01-28 09:12:45.180: E/AndroidRuntime(1766): FATAL EXCEPTION: main
01-28 09:12:45.180: E/AndroidRuntime(1766): java.lang.RuntimeException: Unable to start activity ComponentInfo{www.gurjit.taskmanager/www.gurjit.taskmanager.MainActivity}: android.view.InflateException: Binary XML file line #29: Error inflating class button
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.os.Handler.dispatchMessage(Handler.java:99)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.os.Looper.loop(Looper.java:137)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.app.ActivityThread.main(ActivityThread.java:5103)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at java.lang.reflect.Method.invokeNative(Native Method)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at java.lang.reflect.Method.invoke(Method.java:525)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at dalvik.system.NativeStart.main(Native Method)
01-28 09:12:45.180: E/AndroidRuntime(1766): Caused by: android.view.InflateException: Binary XML file line #29: Error inflating class button
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:707)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.view.LayoutInflater.rInflate(LayoutInflater.java:755)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:267)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.app.Activity.setContentView(Activity.java:1895)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at www.gurjit.taskmanager.MainActivity.onCreate(MainActivity.java:20)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.app.Activity.performCreate(Activity.java:5133)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
01-28 09:12:45.180: E/AndroidRuntime(1766):     ... 11 more
01-28 09:12:45.180: E/AndroidRuntime(1766): Caused by: java.lang.ClassNotFoundException: Didn't find class "android.view.button" on path: DexPathList[[zip file "/data/app/www.gurjit.taskmanager-2.apk"],nativeLibraryDirectories=[/data/app-lib/www.gurjit.taskmanager-2, /vendor/lib, /system/lib]]
01-28 09:12:45.180: E/AndroidRuntime(1766):     at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:53)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.view.LayoutInflater.createView(LayoutInflater.java:559)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.view.LayoutInflater.onCreateView(LayoutInflater.java:652)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:66)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.view.LayoutInflater.onCreateView(LayoutInflater.java:669)
01-28 09:12:45.180: E/AndroidRuntime(1766):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:694)
01-28 09:12:45.180: E/AndroidRuntime(1766):     ... 21 more

Answer 1

您的代码有多个问题：

在java代码中，您忘了转换TextView：

tasklist_view =（TextView）findViewById（R.id.textView2）;
在XML中，将<button>更改为<Button>
在ID属性中，您忘记在分配ID之前加上一个加号：

机器人：ID = “@ + ID / Add按钮”
在RelativeLayout中，如果不声明相对定位，则无法使用视图，因此请将xml更改为：

<TextView
    android:id="@+id/textView1"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/tasks"
    android:textColor="#12ade4"
    android:textSize="20sp" />

<Button
    android:id="@+id/addButton"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/add_button"
    android:textSize="15sp" 
    android:padding="10dp"
    android:layout_alignParentBottom="true"/>

MainActivity中的Android错误？

1 个答案: