使用Android Studio在Google地图上创建浮动按钮时出错

Question

我正在尝试在Google地图上的android studio中创建一个浮动按钮。 该按钮的目的是更新地图上的标记，但是在尝试使其膨胀时会出现以下错误：

    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.kakao/com.example.kakao.MapsActivity}: android.view.InflateException: Binary XML file line #12: Binary XML file line #12: Error inflating class android.support.design.widget.FloatingActionButton
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3297)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3405)
    at android.app.ActivityThread.-wrap12(Unknown Source:0)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1994)
    at android.os.Handler.dispatchMessage(Handler.java:108)
    at android.os.Looper.loop(Looper.java:166)
    at android.app.ActivityThread.main(ActivityThread.java:7523)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:245)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:921)
 Caused by: android.view.InflateException: Binary XML file line #12: Binary XML file line #12: Error inflating class android.support.design.widget.FloatingActionButton
 Caused by: android.view.InflateException: Binary XML file line #12: Error inflating class android.support.design.widget.FloatingActionButton
 Caused by: java.lang.ClassNotFoundException: Didn't find class "android.support.design.widget.FloatingActionButton" on path: DexPathList[[zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/base.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_dependencies_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_resources_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_slice_0_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_slice_1_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_slice_2_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_slice_3_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_slice_4_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_slice_5_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_slice_6_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_slice_7_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_slice_8_apk.apk", zip file "/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/split_lib_slice_9_apk.apk"],nativeLibraryDirectories=[/data/app/com.example.kakao-OUJ-bqVa2zcpC7rS80Bifg==/lib/arm64, /system/lib64, /vendor/lib64, /product/lib64]]
    at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:93)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
    at android.view.LayoutInflater.createView(LayoutInflater.java:613)
    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:801)
    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:741)
    at android.view.LayoutInflater.rInflate(LayoutInflater.java:874)
    at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:835)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
    at androidx.appcompat.app.AppCompatDelegateImpl.setContentView(AppCompatDelegateImpl.java:469)
    at androidx.appcompat.app.AppCompatActivity.setContentView(AppCompatActivity.java:140)
    at com.example.kakao.MapsActivity.onCreate(MapsActivity.java:76)
    at android.app.Activity.performCreate(Activity.java:7383)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1218)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3250)

xml中的按钮：

    <android.support.design.widget.FloatingActionButton
    android:id="@+id/my_fab"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|end"
    android:layout_margin="16dp"
    android:src="@drawable/ic_alert_circle_white_36dp" />

Java中的引用和膨胀：

   FloatingActionButton my_fab = (FloatingActionButton) findViewById(R.id.my_fab);

    my_fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Tocaste el FAB", Snackbar.LENGTH_LONG).show();
        }
    });

我的依赖：

dependencies {
implementation fileTree(include: ['*.jar'], dir: 'libs')
implementation 'com.android.support:appcompat-v7:28.0.0'
implementation 'com.android.support.constraint:constraint-layout:1.1.3'
implementation 'com.google.android.gms:play-services-maps:16.1.0'
implementation 'androidx.appcompat:appcompat:1.0.0-beta01'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
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'
implementation 'com.google.android.gms:play-services-location:16.0.0'
implementation 'com.google.android.material:material:1.0.0'

Answer 1

您应该使用app:srcCompat而不是android:src 。

app:srcCompat="@drawable/ic_alert_circle_white_36dp"

正确的xml将是

 <android.support.design.widget.FloatingActionButton
    android:id="@+id/my_fab"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|end"
    android:layout_margin="16dp"
    app:srcCompat="@drawable/ic_alert_circle_white_36dp" />

Answer 2

您必须将此依赖项添加到gradle ：

implementation 'com.android.support:design:28.0.0'

Answer 3

您正在使用androidx库，因此应在xml中用于FAB的类为：

com.google.android.material.floatingactionbutton.FloatingActionButton

代替 ：

android.support.design.widget.FloatingActionButton