问题描述
我根据YouTube上的课程进行了所有操作，但无法打开该应用程序。如何解决错误？我尝试在虚拟设备上安装不同版本的android，但没有任何帮助。我不明白我做错了什么。尝试通过注释进行一些代码检查。如果将Oncreate注释掉，则会打开一个空活动。
这是MainActivity.java
package com.makar_mikhalchenko.itchat;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.TextView;
import com.firebase.ui.auth.AuthUI;
import com.firebase.ui.database.Firebaselistadapter;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.FirebaseDatabase;
import android.text.format.DateFormat;
import java.util.Objects;
public class MainActivity extends AppCompatActivity {
private static int SIGN_IN_CODE = 1;
private RelativeLayout activity_main;
private Firebaselistadapter<Message> adapter;
private FloatingActionButton sendBtn;
@Override
protected void onActivityResult(int requestCode,int resultCode,@Nullable Intent data) {
super.onActivityResult(requestCode,resultCode,data);
if(requestCode == SIGN_IN_CODE){
if (resultCode == RESULT_OK){
Snackbar.make(activity_main,"Вы авторизованы",Snackbar.LENGTH_LONG).show();
displayAllMessages();
}else{
Snackbar.make(activity_main,"Вы не авторизованы",Snackbar.LENGTH_LONG).show();
finish();
}
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
activity_main = findViewById(R.id.activity_main);
sendBtn = findViewById(R.id.btnSend);
sendBtn.setonClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
EditText textField = findViewById(R.id.messageField);
if (textField.getText().toString() == "")
return;
FirebaseDatabase.getInstance().getReference().push().setValue(
new Message(FirebaseAuth.getInstance().getCurrentUser().getEmail(),textField.getText().toString()));
textField.setText("");
}
});
//пользователь ещё не авторизован
if (FirebaseAuth.getInstance().getCurrentUser() == null)
startActivityForResult(AuthUI.getInstance().createSignInIntentBuilder().build(),SIGN_IN_CODE);
else {
Snackbar.make(activity_main,Snackbar.LENGTH_LONG).show();
displayAllMessages();
}
}
private void displayAllMessages() {
ListView listofMessages = findViewById(R.id.list_of_messages);
adapter = new Firebaselistadapter<Message>(this,Message.class,R.layout.list_item,FirebaseDatabase.getInstance().getReference()) {
@Override
protected void populateView(View v,Message model,int position) {
TextView mess_user,mess_time,mess_text;
mess_user = v.findViewById(R.id.message_user);
mess_time = v.findViewById(R.id.message_time);
mess_text = v.findViewById(R.id.message_text);
mess_user.setText(model.getUserName());
mess_text.setText(model.getTextMessage());
mess_time.setText(DateFormat.format("dd-mm-yy HH:mm:ss",model.getMessageTime()));
}
};
listofMessages.setAdapter(adapter);
}
}
这是activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:id="@+id/activity_main">
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="@+id/btnSend"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="true"
android:src="@drawable/ic_send_button"
android:tint="@android:color/white"
android:layout_alignParentBottom="true"
android:layout_alignParentEnd="true"
android:layout_marginRight="5sp"
android:layout_marginBottom="5sp"
/>
<com.google.android.material.textfield.TextInputLayout
android:id="@+id/text_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentStart="true"
android:layout_toLeftOf="@+id/btnSend">
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/messageField"
android:hint="Введите сообщение"
/>
</com.google.android.material.textfield.TextInputLayout>
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="@+id/text_layout"
android:id="@+id/list_of_messages"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true"
android:divider="@android:color/transparent"
android:dividerHeight="16dp"
android:layout_marginBottom="12dp"
>
</ListView>
</RelativeLayout>
调试问题
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.makar_mikhalchenko.itchat,PID: 8987
java.lang.NoClassDefFoundError: Failed resolution of: Lcom/google/android/gms/common/api/Api$zzf;
at com.google.android.gms.auth.api.Auth.<clinit>(UnkNown Source)
at com.firebase.ui.auth.util.CredentialsAPI.initGoogleapiclient(CredentialsAPI.java:145)
at com.firebase.ui.auth.util.CredentialsAPI.<init>(CredentialsAPI.java:65)
at com.firebase.ui.auth.ui.ChooseAccountActivity.onCreate(ChooseAccountActivity.java:91)
at android.app.Activity.performCreate(Activity.java:6679)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performlaunchActivity(ActivityThread.java:2618)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
Caused by: java.lang.classNotFoundException: Didn't find class "com.google.android.gms.common.api.Api$zzf" on path: DexPathList[[zip file "/data/app/com.makar_mikhalchenko.itchat-1/base.apk"],nativeLibraryDirectories=[/data/app/com.makar_mikhalchenko.itchat-1/lib/x86,/system/lib,/vendor/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
at java.lang.classLoader.loadClass(ClassLoader.java:380)
at java.lang.classLoader.loadClass(ClassLoader.java:312)
at com.google.android.gms.auth.api.Auth.<clinit>(UnkNown Source)
at com.firebase.ui.auth.util.CredentialsAPI.initGoogleapiclient(CredentialsAPI.java:145)
at com.firebase.ui.auth.util.CredentialsAPI.<init>(CredentialsAPI.java:65)
at com.firebase.ui.auth.ui.ChooseAccountActivity.onCreate(ChooseAccountActivity.java:91)
at android.app.Activity.performCreate(Activity.java:6679)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performlaunchActivity(ActivityThread.java:2618)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
I/FA: Tag Manager is not found and thus will not be used
D/FA: Logging event (FE): screen_view(_vs),Bundle[{firebase_event_origin(_o)=auto,firebase_screen_class(_sc)=MainActivity,firebase_screen_id(_si)=-2868454111777039973}]
V/FA: Connection attempt already in progress
V/FA: Connection attempt already in progress
Activity resumed,time: 2583628
V/FA: Screen exposed for less than 1000 ms. Event not sent. time: 444
V/FA: Connection attempt already in progress
Activity paused,time: 2583641
Build.gradle
apply plugin: 'com.android.application'
android {
compileSdkVersion 30
buildToolsversion "30.0.2"
defaultConfig {
applicationId "com.makar_mikhalchenko.itchat"
minSdkVersion 24
targetSdkVersion 30
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'),'proguard-rules.pro'
}
}
}
dependencies {
implementation filetree(dir: "libs",include: ["*.jar"])
implementation 'androidx.appcompat:appcompat:1.2.0'
implementation 'androidx.constraintlayout:constraintlayout:2.0.1'
implementation 'com.google.android.material:material:1.2.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test.ext:junit:1.1.2'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
implementation 'com.google.firebase:firebase-analytics:17.5.0'
implementation 'com.google.android.material:material:1.2.0'
implementation 'com.google.firebase:firebase-auth:19.3.2'
implementation 'com.google.firebase:firebase-database:19.4.0'
implementation 'com.firebaseui:firebase-ui:0.6.2'
implementation 'com.google.android.gms:play-services-auth:18.1.0'
}
//apply plugin: 'com.google.gms.google-services'