java - Android Studio androidx.coordinatorlayout 错误以及如何设置 3Dot Menu？

Question

我有以下问题。我的 android studio 正在显示错误，该错误已写在标题中 Screenshot .我试图在右上角实现漂亮的 3 点菜单。如果有人能告诉我问题是什么，那就太好了......

我在尝试 gradle 时遇到的错误是:

C:\Users\User\AndroidStudioProjects\BluetoothCar\app\src\main\java\com\car\bluetooth\bluetoothcar\MainActivity.java:11: 错误:包 android.support.design.widget 确实不存在
导入 android.support.design.widget.AppBarLayout；


C:\Users\User\AndroidStudioProjects\BluetoothCar\app\src\main\java\com\car\bluetooth\bluetoothcar\MainActivity.java:12: 错误:包 android.support.v7.widget 不不存在
导入 android.support.v7.widget.Toolbar；


我已经尝试导入 v7.widget.toolbar，但它将 v7 标记为红色并表示无法解析符号。

主要 Activity .java :

package com.car.bluetooth.bluetoothcar;

import android.os.Bundle;

import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;

import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;

import android.support.design.widget.AppBarLayout;
import android.support.v7.widget.Toolbar;

import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.SeekBar;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

//SeekBars

private SeekBar seekBarGas;
private TextView textViewGas;

private SeekBar seekBarSteering;
private TextView textViewSteering;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);


    seekBarGas = (SeekBar) findViewById(R.id.seekBarGas);
    textViewGas = (TextView) findViewById(R.id.textViewGas);
    seekBarGas.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
        @Override
        public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
            textViewGas.setText(progress + "  /  " + seekBarGas.getMax());
        }

        @Override
        public void onStartTrackingTouch(SeekBar seekBar) {

        }

        @Override
        public void onStopTrackingTouch(SeekBar seekBar) {
            seekBarGas.setProgress(0);
        }
    });

    seekBarSteering = (SeekBar) findViewById(R.id.seekBarSteering);
    textViewSteering = (TextView) findViewById(R.id.textViewSteering);
    seekBarSteering.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
        @Override
        public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
            textViewSteering.setText(progress + "  /  " + seekBarSteering.getMax());
        }

        @Override
        public void onStartTrackingTouch(SeekBar seekBar) {

        }

        @Override
        public void onStopTrackingTouch(SeekBar seekBar) {
            seekBarSteering.setProgress(3);
        }
    });








}

}

content_main.xml :

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context=".MainActivity"
tools:showIn="@layout/activity_main">

<SeekBar
    android:id="@+id/seekBarGas"
    android:layout_width="237dp"
    android:layout_height="117dp"
    android:layout_marginStart="8dp"
    android:layout_marginLeft="8dp"
    android:layout_marginTop="8dp"
    android:layout_marginBottom="8dp"
    android:max="5"
    android:progress="0"
    android:rotation="-90"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent" />

<TextView
    android:id="@+id/gas_text"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginStart="28dp"
    android:layout_marginLeft="28dp"
    android:layout_marginTop="8dp"
    android:layout_marginBottom="8dp"
    android:text="Gas"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintStart_toStartOf="@+id/seekBarGas"
    app:layout_constraintTop_toTopOf="parent"
    tools:textColor="@android:color/background_dark" />

<TextView
    android:id="@+id/textViewGas"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginStart="32dp"
    android:layout_marginLeft="32dp"
    android:layout_marginTop="8dp"
    android:layout_marginBottom="8dp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/gas_text"
    app:layout_constraintVertical_bias="0.0"
    tools:textColor="@android:color/background_dark" />

<SeekBar
    android:id="@+id/seekBarSteering"
    android:layout_width="199dp"
    android:layout_height="106dp"
    android:layout_marginStart="8dp"
    android:layout_marginLeft="8dp"
    android:layout_marginEnd="8dp"
    android:layout_marginRight="8dp"
    android:layout_marginBottom="4dp"
    android:max="6"
    android:progress="3"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintHorizontal_bias="1.0"
    app:layout_constraintStart_toStartOf="parent" />

<TextView
    android:id="@+id/steeringText"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginStart="8dp"
    android:layout_marginLeft="8dp"
    android:layout_marginTop="160dp"
    android:layout_marginEnd="8dp"
    android:layout_marginRight="8dp"
    android:text="Lenkung"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintHorizontal_bias="0.86"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent"
    tools:textColor="@android:color/background_dark" />

<TextView
    android:id="@+id/textViewSteering"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginStart="8dp"
    android:layout_marginLeft="8dp"
    android:layout_marginEnd="8dp"
    android:layout_marginRight="8dp"
    android:layout_marginBottom="88dp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintHorizontal_bias="0.842"
    app:layout_constraintStart_toStartOf="parent"
    tools:textColor="@android:color/background_dark" />

activity_main.xml :

<androidx.coordinatorlayout.widget.CoordinatorLayout 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"
tools:context=".MainActivity">

<android.support.design.widget.AppBarLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:theme="@style/AppTheme.AppBarOverlay">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:popupTheme="@style/AppTheme.PopupOverlay" />

</android.support.design.widget.AppBarLayout>

<include layout="@layout/content_main" />

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.car.bluetooth.bluetoothcar">

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity
        android:name=".MainActivity"
        android:label="@string/app_name"
        android:screenOrientation="landscape"
        android:theme="@style/AppTheme.NoActionBar">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

Build.grade(应用程序)

apply plugin: 'com.android.application'

android {
compileSdkVersion 27
defaultConfig {
    applicationId "com.car.bluetooth.bluetoothcar"
    minSdkVersion 15
    targetSdkVersion 28
    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 'com.android.support:appcompat-v7:27.1.1'
implementation 'com.android.support:design:27.1.1'
implementation 'com.android.support.constraint:constraint-layout:1.1.2'
implementation 'android.arch.navigation:navigation-fragment:1.0.0-alpha05'
implementation 'android.arch.navigation:navigation-ui:1.0.0-alpha05'

testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

错误:

* What went wrong:
Execution failed for task ':app:processDebugResources'.
> Android resource linking failed
  C:\Users\User\.gradle\caches\transforms-1\files-1.1\appcompat-1.0.0- 
rc01.aar\f57a72ca523e97bfd49e26fe0ca995bd\res\values-v28\values-v28.xml:9:5- 
   12:13: AAPT: error: resource android:attr/dialogCornerRadius not found.

C:\Users\User\AndroidStudioProjects\BluetoothCar\app\build\intermediates\incremental\mergeDebugResources\merged.dir\values-v28\values-v28.xml:11: AAPT: 错误: 资源 android:attr/dialogCornerRadius没有找到。

 C:\Users\User\.gradle\caches\transforms-1\files-1.1\material-1.0.0-rc01.aar\5165e838ec45d5f110381d4afe9056c6\res\values\values.xml:161:5-202: AAPT: error: resource android:attr/fontVariationSettings not found.

  C:\Users\User\.gradle\caches\transforms-1\files-1.1\material-1.0.0-rc01.aar\5165e838ec45d5f110381d4afe9056c6\res\values\values.xml:161:5-202: AAPT: error: resource android:attr/ttcIndex not found.

  error: failed linking references.

Answer 1

对于 androidx 使用以下依赖

dependencies {
    implementation "androidx.coordinatorlayout:coordinatorlayout:1.1.0"
}

引用 - https://developer.android.com/jetpack/androidx/releases/coordinatorlayout