diff --git a/app/build.gradle b/app/build.gradle
index 7dd47a2..7128790 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -2,7 +2,6 @@ apply plugin: 'com.android.application'
 
 android {
     compileSdkVersion 26
-    buildToolsVersion "26.0.2"
 
     defaultConfig {
         applicationId "net.ossrs.yasea.demo"
@@ -23,8 +22,8 @@ android {
 }
 
 dependencies {
-    compile fileTree(dir: 'libx264.libs', include: ['*.jar'])
-    testCompile 'junit:junit:4.12'
-    compile 'com.android.support:appcompat-v7:26.1.0'
-    compile project(path: ':library')
+    implementation fileTree(dir: 'libx264.libs', include: ['*.jar'])
+    testImplementation 'junit:junit:4.12'
+    implementation 'com.android.support:appcompat-v7:26.1.0'
+    implementation project(path: ':library')
 }
diff --git a/app/src/main/java/net/ossrs/yasea/demo/MainActivity.java b/app/src/main/java/net/ossrs/yasea/demo/MainActivity.java
index 445c640..e6d2ea0 100644
--- a/app/src/main/java/net/ossrs/yasea/demo/MainActivity.java
+++ b/app/src/main/java/net/ossrs/yasea/demo/MainActivity.java
@@ -40,10 +40,11 @@ public class MainActivity extends AppCompatActivity implements RtmpHandler.RtmpL
     private Button btnPause;
 
     private SharedPreferences sp;
-    private String rtmpUrl = "rtmp://ossrs.net/" + getRandomAlphaString(3) + '/' + getRandomAlphaDigitString(5);
+    private String rtmpUrl = "rtmp://asia-southeast1-u-01-gw.uizadev.io:1935/push2transcode/918badeb-0c81-46f1-9e91-9a1cc566dc3a?token=28cc0b78538b13a120d1e47fc0c7ce85&ulasId=57ee741f-3daf-11e9-89c5-02c1b5b83c1a";
     private String recPath = Environment.getExternalStorageDirectory().getPath() + "/test.mp4";
 
     private SrsPublisher mPublisher;
+    private SrsCameraView mCameraView;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
diff --git a/build.gradle b/build.gradle
index 610ad07..abc3373 100644
--- a/build.gradle
+++ b/build.gradle
@@ -6,7 +6,7 @@ buildscript {
         google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.0.0'
+        classpath 'com.android.tools.build:gradle:3.3.2'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
diff --git a/library/build.gradle b/library/build.gradle
index cf3b864..26535be 100644
--- a/library/build.gradle
+++ b/library/build.gradle
@@ -2,7 +2,6 @@ apply plugin: 'com.android.library'
 
 android {
     compileSdkVersion 26
-    buildToolsVersion "26.0.2"
 
     defaultConfig {
         minSdkVersion 21
@@ -29,10 +28,10 @@ android {
 }
 
 dependencies {
-    compile fileTree(dir: 'libx264.libs', include: ['*.jar'])
-    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
+    implementation fileTree(dir: 'libx264.libs', include: ['*.jar'])
+    androidTestImplementation('com.android.support.test.espresso:espresso-core:2.2.2', {
         exclude group: 'com.android.support', module: 'support-annotations'
     })
-    compile 'com.android.support:appcompat-v7:26.1.0'
-    testCompile 'junit:junit:4.12'
+    implementation 'com.android.support:appcompat-v7:26.1.0'
+    testImplementation 'junit:junit:4.12'
 }
diff --git a/library/src/main/java/net/ossrs/yasea/SrsCameraView.java b/library/src/main/java/net/ossrs/yasea/SrsCameraView.java
index e67951b..5c659ec 100644
--- a/library/src/main/java/net/ossrs/yasea/SrsCameraView.java
+++ b/library/src/main/java/net/ossrs/yasea/SrsCameraView.java
@@ -1,5 +1,6 @@
 package net.ossrs.yasea;
 
+import android.app.Activity;
 import android.content.Context;
 import android.content.res.Configuration;
 import android.graphics.ImageFormat;
@@ -9,6 +10,7 @@ import android.opengl.GLES20;
 import android.opengl.GLSurfaceView;
 import android.opengl.Matrix;
 import android.util.AttributeSet;
+import android.view.Surface;
 
 import com.seu.magicfilter.base.gpuimage.GPUImageFilter;
 import com.seu.magicfilter.utils.MagicFilterFactory;
@@ -373,7 +375,7 @@ public class SrsCameraView extends GLSurfaceView implements GLSurfaceView.Render
     }
 
     protected Camera openCamera() {
-        Camera camera;
+        Camera camera = null;
         if (mCamId < 0) {
             Camera.CameraInfo info = new Camera.CameraInfo();
             int numCameras = Camera.getNumberOfCameras();
diff --git a/library/src/main/java/net/ossrs/yasea/SrsPublisher.java b/library/src/main/java/net/ossrs/yasea/SrsPublisher.java
index d2b76fb..af3ff25 100644
--- a/library/src/main/java/net/ossrs/yasea/SrsPublisher.java
+++ b/library/src/main/java/net/ossrs/yasea/SrsPublisher.java
@@ -1,5 +1,6 @@
 package net.ossrs.yasea;
 
+import android.hardware.Camera;
 import android.media.AudioRecord;
 import android.media.audiofx.AcousticEchoCanceler;
 import android.media.audiofx.AutomaticGainControl;