Screen flickering and animations not working

[Julia]

Edit: it's not actually flickering, more shaking (only up and down).

Hey,

 

I'm (still) trying to make a vertical platformer game. I'm having a problem here where my screen is flickering and my animations for the player don't work anymore if I press the keys. Also the player won't jump anymore. I'm guessing it has something to do with the gravity or the velocity of the player or the game itself. Any ideas?

 

Platformer.Game = function (game) {this._player;this._stars = null;this._ground = null;this._platforms = null;this._platform = null;this._numberOfPlatforms = 15;this._x = this.x;this._y = this.y;this._cursors = null;this._scoreText = null;this._score = 0;this._locs = [];};Platformer.Game.prototype = {create: function (){this.physics.startSystem(Phaser.Physics.ARCADE);this.add.sprite(0, 0, 'background');this._ground = this.add.sprite(game.world.centerX - 480, game.world.height - 124, 'ground');this.physics.enable(this._ground, Phaser.Physics.ARCADE);this._ground.body.immovable = true;this._player = this.add.sprite(this._x, this._y, 'player');game.physics.enable(this._player, Phaser.Physics.ARCADE);this._player.body.gravity.y = 300;this._player.body.bounce.y = 0.2;this._player.animations.add('walk', [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16], 10, true);this._fontStyle = {font: "40px Roboto", fill: "#fff", align: "center"};Platformer._scoreText = this.add.text(120, 20, "0", this._fontStyle);this._platforms = this.add.group();for (var i = 0; i < 20; i++) {this.createUniqueLocation();}this._platforms.sort();game.camera.follow(this._player);},managePause: function () {this.game.paused = true;var pausedText = this.add.text(100, 250, "Game paused. Click anywhere to continue.", this._fontStyle);this.input.onDown.add(function(){pausedText.destroy();this.game.paused = false;}, this);},update: function () {if (game.input.keyboard.isDown(Phaser.Keyboard.LEFT)){this._player.x -= 10;this._player.animations.play('walk');}if (game.input.keyboard.isDown(Phaser.Keyboard.RIGHT)){this._player.x += 10;this._player.animations.play('walk');}if (game.input.keyboard.isDown(Phaser.Keyboard.UP) && this._player.body.blocked.down) {this._player.y -= 10;this._player.animations.play('walk');}else {this._player.frame = 0;}this._platforms.sort('y', Phaser.Group.SORT_ASCENDING);game.physics.arcade.collide(this._player, this._ground);},createUniqueLocation: function () {do {var x = this.math.snapTo(game.world.randomX, 300) / 100;var y = this.math.snapTo(game.world.randomY, 75, this._player.y - 100) / 75;if (y > 35) {y = 35;}var idx = (y * 35) + x;}while (this._locs.indexOf(idx) !== - 1)this._locs.push(idx);this._platforms.create(x * 200, y *75, 'platform', this.rnd.integerInRange(0, 25));}};

[Julia]

Any way I could express myself clearer? Really need help! :-)