android - 迁移到 androidx 后未显示 android XML 预览
问题描述
我正在开发一个项目，我最近使用重构将整个项目更新为 androidx > 迁移到 andoidx，但现在它没有显示 XML 设计预览，只是说“等待构建完成”，尽管我构建 apk 并没有任何错误检查但应用程序运行良好只是预览不显示。
以下是 build.gradle 的代码
android {
compileSdkVersion 29
defaultConfig {
applicationId "abc.example.xyz"
minSdkVersion 19
targetSdkVersion 29
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'androidx.appcompat:appcompat:1.0.0'
implementation 'androidx.cardview:cardview:1.0.0'
implementation 'androidx.recyclerview:recyclerview:1.0.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'com.google.android.material:material:1.0.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test.ext:junit:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.0'
}
主要活动java
import android.content.Intent;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import androidx.appcompat.widget.Toolbar;
import androidx.cardview.widget.CardView;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
public class Home extends AppCompatActivity {
CardView tuts,prog,iq,quiz;
// private InterstitialAd mInterstitialAd;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
Toolbar toolbar=findViewById(R.id.toolbar);
toolbar.inflateMenu(R.menu.menu_video);
setSupportActionBar(toolbar);
tuts=(CardView) findViewById(R.id.Cview_tuts);
prog=(CardView) findViewById(R.id.cView_prog);
iq=(CardView) findViewById(R.id.Cview_IQ);
quiz=(CardView) findViewById(R.id.cView_quiz);
/*
mInterstitialAd = new InterstitialAd(this);
mInterstitialAd.setAdUnitId("");
mInterstitialAd.loadAd(new AdRequest.Builder().build());*/
prog.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent=new Intent(Home.this,TutsActivity.class);
startActivity(intent);
// adload();
}
});
tuts.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent=new Intent(Home.this,ProActivity.class);
startActivity(intent);
// adload();
}
});
iq.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent=new Intent(Home.this,IqActivity.class);
startActivity(intent);
// adload();
}
});
quiz.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent=new Intent(Home.this,MainActivity.class);
startActivity(intent);
// adload();
}
});
}
/* public void adload()
{
if (mInterstitialAd.isLoaded()) {
mInterstitialAd.show();
} else {
Log.d("TAG", "The interstitial wasn't loaded yet.");
}
}*/
}
XML
<?xml version="1.0" encoding="utf-8"?>
<androidx.appcompat.widget.LinearLayoutCompat 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:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".Home">
<androidx.appcompat.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:gravity="left"
android:theme="@style/ThemeOverlay.AppCompat.Light"
app:popupTheme="@color/colorPrimaryDark"
android:background="@color/colorPrimaryDark"
app:title="@string/app_name"
app:titleTextColor="#ffffff"
/>
<androidx.appcompat.widget.LinearLayoutCompat
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
android:orientation="vertical">
<androidx.cardview.widget.CardView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
app:cardElevation="10dp"
android:outlineAmbientShadowColor="#000000"
android:outlineSpotShadowColor="#000000"
>
<androidx.appcompat.widget.LinearLayoutCompat
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/drawable_purple_gradient"
android:gravity="center_vertical|center_horizontal"
>
<androidx.appcompat.widget.AppCompatImageView
android:id="@+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@mipmap/java" />
</androidx.appcompat.widget.LinearLayoutCompat>
</androidx.cardview.widget.CardView>
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
android:fillViewport="true"
android:paddingLeft="10dp"
android:paddingRight="10dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="top"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:weightSum="2">
<androidx.cardview.widget.CardView
android:id="@+id/Cview_tuts"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_margin="10dp"
android:layout_marginVertical="1dp"
android:layout_weight="1"
android:clickable="true"
android:foreground="?android:attr/selectableItemBackground">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/circle_cyan"
android:gravity="center"
android:orientation="vertical">
<ImageView
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:paddingBottom="5dp"
app:srcCompat="@mipmap/tut" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/colorBG"
android:orientation="vertical">
<TextView
android:id="@+id/textView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="5dp"
android:gravity="center_horizontal"
android:text="Tutorials"
android:textColor="#313131"
android:textSize="14sp"
android:textStyle="bold" />
</LinearLayout>
</LinearLayout>
</androidx.cardview.widget.CardView>
<androidx.cardview.widget.CardView
android:id="@+id/cView_prog"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_margin="10dp"
android:layout_weight="1"
android:clickable="true"
android:foreground="?android:attr/selectableItemBackground"
app:cardBackgroundColor="?attr/colorButtonNormal">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/circle_purple"
android:gravity="center"
android:orientation="vertical">
<ImageView
android:id="@+id/imageView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:paddingBottom="5dp"
app:srcCompat="@mipmap/prog" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/colorBG"
android:orientation="vertical">
<TextView
android:id="@+id/textView2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="5dp"
android:gravity="center_horizontal"
android:text="Programs"
android:textColor="#313131"
android:textSize="14sp"
android:textStyle="bold" />
</LinearLayout>
</LinearLayout>
</androidx.cardview.widget.CardView>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:weightSum="2">
<androidx.cardview.widget.CardView
android:id="@+id/Cview_IQ"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_margin="10dp"
android:layout_marginVertical="1dp"
android:layout_weight="1"
android:clickable="true"
android:foreground="?android:attr/selectableItemBackground"
app:cardBackgroundColor="?attr/colorButtonNormal">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/circle_pink"
android:gravity="center"
android:orientation="vertical">
<ImageView
android:id="@+id/imageView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:paddingBottom="5dp"
app:srcCompat="@mipmap/iques" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/colorBG"
android:orientation="vertical">
<TextView
android:id="@+id/textView3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="5dp"
android:gravity="center_horizontal"
android:text="Questions"
android:textColor="#313131"
android:textSize="14sp"
android:textStyle="bold" />
</LinearLayout>
</LinearLayout>
</androidx.cardview.widget.CardView>
<androidx.cardview.widget.CardView
android:id="@+id/cView_quiz"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_margin="10dp"
android:layout_weight="1"
android:clickable="true"
android:foreground="?android:attr/selectableItemBackground"
app:cardBackgroundColor="?attr/colorButtonNormal">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/circle_green"
android:gravity="center"
android:orientation="vertical">
<ImageView
android:id="@+id/imageView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:paddingBottom="5dp"
app:srcCompat="@mipmap/quiz" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/colorBG"
android:orientation="vertical">
<TextView
android:id="@+id/textView4"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="5dp"
android:gravity="center_horizontal"
android:text="Quiz"
android:textColor="#313131"
android:textSize="14sp"
android:textStyle="bold" />
</LinearLayout>
</LinearLayout>
</androidx.cardview.widget.CardView>
</LinearLayout>
</LinearLayout>
</ScrollView>
</androidx.appcompat.widget.LinearLayoutCompat>
</androidx.appcompat.widget.LinearLayoutCompat>
解决方案
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