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How to Resolve the Most Common Errors in Android Studio

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How to Resolve the Most Common Errors in Android Studio

Learn how to decipher the various common error messages in Android Studio and how to prevent and solve them.

· Performance Zone ·
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Testing is a vital piece of Android improvement, enabling you to resolve bugs, errors, and execution issues that might prowl in your application before you release it to the population.

Each time you experience an error, Android creates an error message and either shows that message as a feature of Android Studio's Logcat Monitor or as an exchange on the device you're using to test your application.

These error messages are normally short and to the point, and at first look, may not appear to be all that supportive. In any case, these messages really contain all the data you have to get your task back on track — you simply need to know how to decode them!

In this article, we will investigate the 13 error messages you're well on the way to experience when building up any Android application. We'll be investigating what every one of these error messages implies, analyzing all the conceivable reasons why you may experience every error and, in particular, directions on how you can resolve them.

R.layout.main Cannot Be Found/Cannot Resolve Symbol R

This error is caused when Android Studio can’t generate your R.java file correctly, and it can often crop up out of nowhere — one minute everything will be working fine, and the next minute every part of your project is failing to compile. To make matters worse, when Android Studio encounters the R.layout error, it’ll usually flag all your layout resource files as containing errors, which makes it difficult to know where to start looking for the source of the error.

Often, the most effective solution is the simplest: clean and rebuild your project. Select Build > Clean Project from the Android Studio toolbar, wait a few moments, and then build your project by selecting Build > Rebuild Project.

If a single clean/rebuild cycle doesn’t work, try repeating this process a few times, as some developers have reported positive results after completing multiple clean/rebuild cycles in quick succession.

If you encounter this error after moving some files and directories around, then it’s possible that the R.layout error is being caused by a mismatch between Android Studio’s cache and your project’s current layout. If you suspect this may be the case, then select File > Invalidate Caches / Restart > Invalidate and Restart from Android Studio’s toolbar.

Issues with the names of your resources can also prevent the R.java file from being created correctly, so check that you don't have multiple resources with the same name and that none of your file names contain invalid characters. Android Studio only supports lowercase a-z, 0-9, full stops and underscores, and a single invalid character can cause an R.layout error across your entire project, even if you don’t actually use this resource anywhere in your project!

If you do identify and resolve an error, but Android Studio is still displaying the R.layout error, then you may need to complete a clean/rebuild cycle before Android Studio properly registers your changes.

Navigate to File  Project structure  SDK Location and select the Use embedded JDK checkbox

Too Many Field References….Max Is 65,536

When you compile your app, the APK contains executable bytecode files in the form of Dalvik Executable (DEX) bytecode files. The DEX specification states that a single DEX file can reference a maximum of 65,536 methods, and if you encounter the Too many fields… error then it means your app has gone over this limit. Note that this is a limitation on the number of methods your project references, and not the number of methods your project defines.

If you encounter this error, then you can either:

  • Reduce the number of references in your project. One of the most effective ways of trimming your method references is to review your application’s dependencies, as these are often one of the biggest contributors of method references.
  • Configure your app to use more than one DEX file, by enabling multidex.

The process of enabling multidex support will vary depending on the versions of Android your project supports.

If you’re targeting Android 5.0 or higher, then the first step is opening your module-level build.gradle file and setting multiDexEnabled to true:

android {
 defaultConfig {
  minSdkVersion 21 multiDexEnabled true

However, if your minSdkVersion is 20 or lower, then you’ll need to add the multiDexEnabled true attribute and then add the multidex support library as a project dependency:

dependencies {
 compile 'com.android.support:multidex:1.0.1'
}

The next step depends on whether or not you’re overriding the Application class.

If your project does override the Application class, then open your manifest and add the following to the <application> tag:

< application android: name = "android.support.multidex.MultiDexApplication" > ......

If your project doesn’t override the Application class, then you’ll need to extend MultiDexApplicationinstead:

publicclassMyApplication extendsMultiDexApplication

Finally, if you do override the Application class but can’t change the base class, then you can enable multidex by overriding the attachBaseContext() method and calling MultiDex.install(this), for example:

@Override
protected
void
attachBaseContext(Context base) {
 super.attachBaseContext(base);
 MultiDex.install(this);
}


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Topics:
android ,java ,android studio ,mobile app development ,performance ,tutorial ,errors

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