Android Studio学习Android开发踩坑

鼠标滚轮+Ctrl放大缩小编辑区代码字体的设置

初学者运行第一个项目运行时出错

org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:javaPreCompileDebug'.

Caused by: org.gradle.api.internal.artifacts.ivyservice.DefaultLenientConfiguration$ArtifactResolveException: Could not resolve all files for configuration ':app:debugCompileClasspath'.
	at org.gradle.api.internal.artifacts.configurations.DefaultConfiguration.rethrowFailure(DefaultConfiguration.java:1195)
	at org.gradle.api.internal.artifacts.configurations.DefaultConfiguration.access$2100(DefaultConfiguration.java:138)
	at org.gradle.api.internal.artifacts.configurations.DefaultConfiguration$ConfigurationFileCollection.getFiles(DefaultConfiguration.java:1170)
	at org.gradle.api.internal.file.AbstractFileCollection.iterator(AbstractFileCollection.java:72)
	at org.gradle.internal.snapshot.impl.DefaultFileSystemSnapshotter$FileCollectionLeafVisitorImpl.visitCollection(DefaultFileSystemSnapshotter.java:240)
	at org.gradle.api.internal.file.AbstractFileCollection.visitLeafCollections(AbstractFileCollection.java:233)
	at org.gradle.api.internal.file.CompositeFileCollection.visitLeafCollections(CompositeFileCollection.java:205)
	at org.gradle.internal.snapshot.impl.DefaultFileSystemSnapshotter.snapshot(DefaultFileSystemSnapshotter.java:126)
	at org.gradle.internal.fingerprint.impl.AbstractFileCollectionFingerprinter.fingerprint(AbstractFileCollectionFingerprinter.java:48)
	at org.gradle.api.internal.tasks.execution.DefaultTaskFingerprinter.fingerprintTaskFiles(DefaultTaskFingerprinter.java:46)
	at org.gradle.api.internal.tasks.execution.ResolveBeforeExecutionStateTaskExecuter.createExecutionState(ResolveBeforeExecutionStateTaskExecuter.java:93)
	at org.gradle.api.internal.tasks.execution.ResolveBeforeExecutionStateTaskExecuter.execute(ResolveBeforeExecutionStateTaskExecuter.java:73)
	at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:62)
	at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:108)
	at org.gradle.api.internal.tasks.execution.ResolveBeforeExecutionOutputsTaskExecuter.execute(ResolveBeforeExecutionOutputsTaskExecuter.java:67)
	at org.gradle.api.internal.tasks.execution.ResolveAfterPreviousExecutionStateTaskExecuter.execute(ResolveAfterPreviousExecutionStateTaskExecuter.java:46)
	at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:94)
	at org.gradle.api.internal.tasks.execution.FinalizePropertiesTaskExecuter.execute(FinalizePropertiesTaskExecuter.java:46)
	at org.gradle.api.internal.tasks.execution.ResolveTaskExecutionModeExecuter.execute(ResolveTaskExecutionModeExecuter.java:95)
	at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:57)
	at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:56)
	at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:36)

清除.gradle目录下的caches文件夹，重启Android Studio

报错

Activity supporting ACTION_VIEW is not set as BROWSABLE

解决，加入如下这行代码即可

                <category android:name="android.intent.category.BROWSABLE"/>

报错

报错

Version 28(intended for Android Pie and below)is the last version of legacy support library,so we recommend that you migrate to AndroidX libraries when using Android Q and moving forward.

www.mamicode.com/info-detail…

《第一行代码》百分比布局 ：error: attribute layout_heightPercent （XXX）not found

implementation 'androidx.percentlayout:percentlayout:1.0.0'

www.cnblogs.com/hbuwyg/p/11… developer.android.google.cn/jetpack/and…

PercentFrameLayout已弃用，但还能用

控件必须有

    android:layout_width="match_parent"
    android:layout_height="wrap_content"

RecyclerView

implementation 'androidx.recyclerview:recyclerview:1.0.0'

<androidx.recyclerview.widget.RecyclerView/>

《第一行代码纠错》

报错

第五章

自动添加