我正在开发一个应用程序,但我遇到了一段代码的问题。同一段代码给了我几个不同页面的相同错误。
代码如下:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
buttonSignIn = (Button) findViewById(R.id.buttonSignIN);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG).setAction("Action", null).show();
buttonSignIn.setOnClickListener(this);
}
});
}}
它在下面的行上给出了一个错误,说它无法解析符号fab FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
您可能删除了activity_main中的fab:
如果是这种情况,并且你真的不需要fab,你可能只需要删除这段代码:
buttonSignIn = (Button) findViewById(R.id.buttonSignIN);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG).setAction("Action", null).show();
buttonSignIn.setOnClickListener(this);
}
});
添加支持:在build.gradle:module app中设计依赖项,这将解决它
compile 'com.android.support:design:26.+'
将如下所示:
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile 'com.android.support:appcompat-v7:26.+'
compile 'com.android.support.constraint:constraint-layout:1.0.2'
compile 'com.android.support:design:26.+'
testCompile 'junit:junit:4.12'
}