布局文件:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="org.androidtown.sampledialog.MainActivity">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="80dp"
android:text="버튼을 누르면 대화상자가 뜹니다."
android:textSize="24dp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="50dp"
android:text="띄우기"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView" />
</android.support.constraint.ConstraintLayout>
MainActivity:
package org.androidtown.sampledialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
TextView textView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
textView = (TextView) findViewById(R.id.textView);
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
showMessage();
}
});
}
private void showMessage() {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("안내");
builder.setMessage("종료하시겠습니까?");
builder.setIcon(android.R.drawable.ic_dialog_alert);
builder.setPositiveButton("예", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
String message = "예 버튼이 눌렀습니다.";
textView.setText(message);
}
});
builder.setNeutralButton("취소",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
String message = "취소 버튼이 눌렸습니다.";
textView.setText(message);
}
});
builder.setNegativeButton("아니오", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
String message = "아니오 버튼이 눌렸습니다.";
textView.setText(message);
}
});
AlertDialog dialog = builder.create();
dialog.show();
}
}
我无法构建我的第一个应用。我应该怎么做? 这是我的logcat,xml和java代码。
引起:java.lang.ClassNotFoundException:没找到类 &#34; android.support.v7.app.AppCompatActivity&#34;在路径上:DexPathList [[zip file&#34; /data/app/org.androidtown.sampledialog-1/base.apk" ;,zip文件 &#34; /data/app/org.androidtown.sampledialog-1/split_lib_slice_0_apk.apk" ;, zip文件 &#34; /data/app/org.androidtown.sampledialog-1/split_lib_slice_1_apk.apk" ;, zip文件 &#34; /data/app/org.androidtown.sampledialog-1/split_lib_slice_2_apk.apk" ;, zip文件 &#34; /data/app/org.androidtown.sampledialog-1/split_lib_slice_3_apk.apk" ;, zip文件 &#34; /data/app/org.androidtown.sampledialog-1/split_lib_slice_4_apk.apk" ;, zip文件 &#34; /data/app/org.androidtown.sampledialog-1/split_lib_slice_5_apk.apk" ;, zip文件 &#34; /data/app/org.androidtown.sampledialog-1/split_lib_slice_6_apk.apk" ;, zip文件 &#34; /data/app/org.androidtown.sampledialog-1/split_lib_slice_7_apk.apk" ;, zip文件 &#34; /data/app/org.androidtown.sampledialog-1/split_lib_slice_8_apk.apk" ;, zip文件 &#34; /data/app/org.androidtown.sampledialog-1/split_lib_slice_9_apk.apk"],nativeLibraryDirectories = [/数据/应用/ org.androidtown.sampledialog-1 / LIB / 86, / system / lib,/ vendor / lib]] 在 dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56) at java.lang.ClassLoader.loadClass(ClassLoader.java:380) 在java.lang.ClassLoader.loadClass(ClassLoader.java:312) ......还有15个
答案 0 :(得分:1)
此解决方案适合我。
转到Android工作室文件 - &gt;使缓存/重新启动和首选项无效 - &gt;构建执行部署 - &gt;即时运行 - &gt;好的。取消选中重启活动和代码更改。