Android实现拍照及图片裁剪（6.0以上权限处理及7.0以上文件管理）

最近做项目中涉及到了图片相关功能 ，在使用安卓6.0手机及7.1手机拍照时，遇到了因权限及文件管理导致程序崩溃等问题。
 刚好把功能修改完，把代码简单地贴一下，方便以后使用。

—-主界面 代码 ——

public class mainactivity extends appcompatactivity {
  //拍照按钮
  private button take_photo;
  //显示裁剪后的图片
  private imageview photo_iv;
  private static final int permissions_for_take_photo = 10;
  //图片文件路径
  private string picpath;
  //图片对应uri
  private uri photouri;
  //拍照对应requestcode
  public static final int select_pic_by_tack_photo = 1;
  //裁剪图片
  private static final int crop_picture = 3;


  @override
  protected void oncreate(bundle savedinstancestate) {
    super.oncreate(savedinstancestate);
    setcontentview(r.layout.activity_main);
    take_photo = (button) findviewbyid(r.id.take_photo);
    photo_iv = (imageview) findviewbyid(r.id.photo_iv);
    take_photo.setonclicklistener(new view.onclicklistener() {
      @override
      public void onclick(view view) {
        //小于6.0版本直接操作
        if (build.version.sdk_int < 23) {
          takepictures();
        } else {
          //6.0以后权限处理
          permissionform();
        }
      }
    });
  }

  @override
  protected void onactivityresult(int requestcode, int resultcode, intent data) {
    super.onactivityresult(requestcode, resultcode, data);
    if (resultcode == activity.result_ok) {
      if (requestcode == select_pic_by_tack_photo) {
        string[] pojo = {mediastore.images.media.data};
        cursor cursor = managedquery(photouri, pojo, null, null, null);
        if (cursor != null) {
          int columnindex = cursor.getcolumnindexorthrow(pojo[0]);
          cursor.movetofirst();
          picpath = cursor.getstring(columnindex);
          if (build.version.sdk_int < 14) {
            cursor.close();
          }
        }
        if (picpath != null && (picpath.endswith(".png") || picpath.endswith(".png") || picpath.endswith(".jpg") || picpath.endswith(".jpg"))) {
          photouri = uri.fromfile(new file(picpath));
          if (build.version.sdk_int > 23) {
            photouri = fileprovider.geturiforfile(this, "com.innopro.bamboo.fileprovider", new file(picpath));
            cropforn(picpath, crop_picture);
          } else {
            startphotozoom(photouri, crop_picture);
          }
        } else {
          //错误提示
        }
      }
      if (requestcode == crop_picture) {
        if (photouri != null) {
          bitmap bitmap = bitmapfactory.decodefile(picpath);
          if (bitmap != null) {
            photo_iv.setimagebitmap(bitmap);
          }
        }
      }
    }
  }

  /**
   * 拍照获取图片
   */
  private void takepictures() {
    //执行拍照前，应该先判断sd卡是否存在
    string sdstate = environment.getexternalstoragestate();
    if (sdstate.equals(environment.media_mounted)) {
      intent intent = new intent(mediastore.action_image_capture);
      contentvalues values = new contentvalues();
      photouri = getcontentresolver().insert(mediastore.images.media.external_content_uri, values);
      intent.putextra(mediastore.extra_output, photouri);
      startactivityforresult(intent, select_pic_by_tack_photo);
    } else {
      toast.maketext(this, "手机未插入内存卡", toast.length_long).show();
    }
  }


  /**
   * 图片裁剪，参数根据自己需要设置
   *
   * @param uri
   * @param reque_code_crop
   */
  private void startphotozoom(uri uri,
                int reque_code_crop) {
    int dp = 500;
    intent intent = new intent("com.android.camera.action.crop");
    intent.setdataandtype(uri, "image/*");
    // 下面这个crop=true是设置在开启的intent中设置显示的view可裁剪
    intent.putextra("crop", "true");
    intent.putextra("scale", true);// 去黑边
    intent.putextra("scaleupifneeded", true);// 去黑边
    // aspectx aspecty 是宽高的比例
    intent.putextra("aspectx", 4);//输出是x方向的比例
    intent.putextra("aspecty", 3);
    intent.putextra("outputx", 600);//输出x方向的像素
    intent.putextra("outputy", 450);
    intent.putextra("outputformat", bitmap.compressformat.jpeg.tostring());
    intent.putextra("nofacedetection", true);
    intent.putextra(mediastore.extra_output, uri);
    intent.putextra("return-data", false);//设置为不返回数据
    startactivityforresult(intent, reque_code_crop);
  }

  /**
   * 7.0以上版本图片裁剪操作
   *
   * @param imagepath
   * @param reque_code_crop
   */
  private void cropforn(string imagepath, int reque_code_crop) {
    uri cropuri = getimagecontenturi(new file(imagepath));
    intent intent = new intent("com.android.camera.action.crop");
    intent.setdataandtype(cropuri, "image/*");
    intent.putextra("crop", "true");
    //输出是x方向的比例
    intent.putextra("aspectx", 4);
    intent.putextra("aspecty", 3);
    // outputx outputy 是裁剪图片宽高
    intent.putextra("outputx", 600);
    intent.putextra("outputy", 450);
    intent.putextra("scale", true);
    intent.putextra("return-data", false);
    intent.putextra(mediastore.extra_output, cropuri);
    intent.putextra("outputformat", bitmap.compressformat.jpeg.tostring());
    intent.putextra("nofacedetection", true);
    startactivityforresult(intent, reque_code_crop);
  }

  private uri getimagecontenturi(file imagefile) {
    string filepath = imagefile.getabsolutepath();
    cursor cursor = getcontentresolver().query(
        mediastore.images.media.external_content_uri,
        new string[]{mediastore.images.media._id},
        mediastore.images.media.data + "=? ",
        new string[]{filepath}, null);

    if (cursor != null && cursor.movetofirst()) {
      int id = cursor.getint(cursor
          .getcolumnindex(mediastore.mediacolumns._id));
      uri baseuri = uri.parse("content://media/external/images/media");
      return uri.withappendedpath(baseuri, "" + id);
    } else {
      if (imagefile.exists()) {
        contentvalues values = new contentvalues();
        values.put(mediastore.images.media.data, filepath);
        return getcontentresolver().insert(
            mediastore.images.media.external_content_uri, values);
      } else {
        return null;
      }
    }
  }

  /**
   * 安卓6.0以上版本权限处理
   */
  private void permissionform() {
    if (contextcompat.checkselfpermission(this,
        manifest.permission.camera) != packagemanager.permission_granted || contextcompat.checkselfpermission(this,
        manifest.permission.write_external_storage) != packagemanager.permission_granted || contextcompat.checkselfpermission(this,
        manifest.permission.read_external_storage) != packagemanager.permission_granted) {

      activitycompat.requestpermissions(this,
          new string[]{manifest.permission.camera, manifest.permission.write_external_storage, manifest.permission.read_external_storage},
          permissions_for_take_photo);
    } else {
      takepictures();
    }
  }

  @override
  public void onrequestpermissionsresult(int requestcode,
                      @nonnull string[] permissions, @nonnull int[] grantresults) {

    if (requestcode == permissions_for_take_photo) {
      if (grantresults[0] == packagemanager.permission_granted) {
        takepictures();
      }
      return;
    }
    super.onrequestpermissionsresult(requestcode, permissions, grantresults);
  }

}

–主界面布局——–

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.constraintlayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:app="http://schemas.android.com/apk/res-auto"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  tools:context="com.innopro.improve.mainactivity">

  <button
    android:id="@+id/take_photo"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="拍照"
    android:textsize="18sp"
    app:layout_constraintleft_toleftof="parent"
    app:layout_constraintright_torightof="parent"
    app:layout_constrainttop_totopof="parent" />

  <imageview
    android:id="@+id/photo_iv"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@mipmap/ic_launcher"
    app:layout_constraintleft_toleftof="parent"
    app:layout_constraintright_torightof="parent"
    app:layout_constrainttop_tobottomof="@id/take_photo" />

</android.support.constraint.constraintlayout>

–androidmanifest.xml添加provider——–

   <provider
      android:name="android.support.v4.content.fileprovider"
      android:authorities="com.innopro.improve.fileprovider"
      android:exported="false"
      android:granturipermissions="true">
      <meta-data
        android:name="android.support.file_provider_paths"
        android:resource="@xml/file_paths" />
    </provider>

–资源文件下添加xml文件夹及file_paths文件——–

<?xml version="1.0" encoding="utf-8"?>
<resources>
  <paths>
    <external-path
      name="camera_photos"
      path="" />
  </paths>
</resources>

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。